Change your MTU under Vista, Windows 7 or Windows 8

October 23, 2009 – 21:11

I have been updating this blog post over the years since I first discovered the issue with my computer in Windows Vista, now I am on Windows 8 and also on FTTC broadband; Path MTU Discovery seems to just work. I have tested the process so the approach and the commands still work in Windows 8, I however no longer need to use this process personally.

For some reason that has escaped me Path MTU Discovery (PMTUD) in Windows just doesn’t seem to figure out the MTU for a given path (something to do with routers being poorly configured to not respond to ICMP requests). So Windows uses the default. For the most part this doesn’t affect anyone, however if it does affect you, it really annoys you. Failure of PMTUD will result in some websites not loading correctly, having trouble connecting to normally reliable online services and general Internet weirdness.

The resolution is to set your default MTU to one lower than the Ethernet default of 1500. Here is how:

Step 1: Find your MTU

From an elevated Command Prompt in Vista/Windows 7 or the same elevated Command Prompt in Windows 8 enter the following command:

netsh interface ipv4 show subinterfaces

You should get something like this

MTU         MediaSenseState  Bytes In    Bytes Out  Interface
----------  ---------------  ---------   ---------  -------------
4294967295  1                0           13487914   Loopback Pseudo-Interface 1
1500        1                3734493902  282497358  Local Area Connection

If you are using Ethernet cable you will be looking for “Local Area Connection” or “Ethernet”. If you are using Wireless you will be looking for “Wireless Network Connection”. The MTU is in the first column.

Step 2: Find out what it should be

In the Command Prompt type:

ping www.cantreachthissite.com -f -l 1472

The host name should be a site you can not reach, -f marks the packet as one that should not be fragmented the -l 1472 sets the size of the packet (1472 = Ethernet Default MTU – Packet Header, where the Ethernet Default MTU is 1500 and the Packet Header is 28 bytes)

If the packet can’t be sent because it would need to be fragmented you will get something similar to this:

Packet needs to be fragmented but DF set.

Keep trying lower packet sizes by 10 (i.e. -l 1460, 1450, 1440, etc.) until you get a successful ping request. Raise your packet sizes by one until you get a “Packet needs to be fragmented but DF set.”. The last successful value plus 28 will be your MTU value.

In my case a packet size of 1430 succeeds but 1431 fails, so 1430 + 28 = 1458.

Step 3: Set your MTU

Now you have identified the interface you need to change and the ideal MTU for you, now it is time to make the change. Again from an elevated Command Prompt type the following replacing my MTU of 1458 with your own value:

netsh interface ipv4 set subinterface "Local Area Connection" mtu=1458 store=persistent

Or if you are using a Wireless connection:

netsh interface ipv4 set subinterface "Wireless Network Connection" mtu=1458 store=persistent

If all has gone well you should have a perfectly working internet connection.

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    1. 148 Responses to “Change your MTU under Vista, Windows 7 or Windows 8”

    2. Exactly the right answer. I’ve seen sites that recommend the netsh but offer no procedure to determine the correct value. Others have you hacking the registry.
      Thanks.

      By Rich on Feb 14, 2010

    3. This procedure works fine on Vista, but not on my Windows 7 machine, there is no “ipv4″ on my machine, only “ip”.

      Tried variations, but I haven’t managed to get anything to work, thought “ping site -f -l 1430″ shows that this is the route for solving my internet access problems…

      By Chops on Apr 6, 2010

    4. @Chops: What is the result of the command `netsh interface ipv4 show subinterfaces` is there anything special about your setup? do you use a standard ethernet to connect to the internet or are you using PPPoE or similar?

      By Richard Slater on Apr 10, 2010

    5. Thank you Richard, for your clear and concise instructions — you saved me from an internetless hell.

      By thegreatunwashed on Apr 13, 2010

    6. and what if OS is not Windows Vista or 7 an dalso modme is not having MTU like in huawei

      By wajiha on Apr 17, 2010

    7. @wajiah, Microsoft has a HOW TO on changing the MTU under XP ( http://support.microsoft.com/kb/826159 ). If the connection your Huawei modem doesn’t have a MTU property it is doing something slightly different, what that is I wouldn’t like to guess.

      By Richard Slater on Apr 17, 2010

    8. Hello,
      I’ve got a problem.
      When ever I try to upload a file more than 100KB in http, the network connection of my computer stop (disconnect), can’t event login to router
      I have to disable the Network Connection and then enable again to make everything work again
      I ask some friends, they tell me try to reset the MTU.
      I use you command and see that my MTU is 1500, but when use this tool speedguide.net/analyzer.php, the MTU result is 1440
      And I can’t ping any site althought I still can access it in the Internet Browser
      I use windows 7 pro
      Can you please help me to solve this problem?

      By soulofdark on Jun 21, 2010

    9. That sounds more like it is an issue with the router than with Windows 7. Have you got another router you could try? It is possible that the router doesn’t handle some setting or other, however what that setting may be I do not know. I can highly recommend Super User as a great place to get your question answered. When you do post on Super User post back here with a link to help others who may be having a similar problem.

      By Richard Slater on Jun 21, 2010

    10. ping requested could not find host http://www.cantreachthissite.com please check the name and try again
      what does that mean and what should i do?

      By chinaman88 on Jul 6, 2010

    11. You need to use a site that dosn’t work for you, http://www.cantreachthissite.com was simply a place holder. Sites that you can’t reach vary depending on network configuration.

      By Richard Slater on Jul 6, 2010

    12. i also have problem with some websites
      after i did step 2 i had an error message it says general failure 4x. please help

      By chinaman88 on Jul 7, 2010

    13. got it. found out that its my software thats blocking the website..
      thanks so much

      By chinaman88 on Jul 7, 2010

    14. Thank you very much,

      And I’m lucky this is one of the few sites that worked, since all other links that google provided on how to change my MTU didn’t open, cause of mtu problems :P

      and this is a much nicer solution than those manual REG fixes.

      By zidar on Aug 9, 2010

    15. Hi I tried your suggestion but now after rebooting when I run an elevated command prompt it appears that the “d” key is stuck down.It isn’t but if I go to type in to Goole search it doe’s the same!Any ideas? Oh if I run Malwarebytes while trying the problen stop’s but it doesn’t find any problems and it only happened after I rebooted! Thanks

      By Doubleg on Sep 10, 2010

    16. have you tried a different keyboard? it is possible that something has got under one of the keys.

      By Richard Slater on Sep 11, 2010

    17. Hi ….

      I am facing the similar issue for one particular website that I could access it before a month but not now anymore.

      I have windows 7 and have tried the way mentioned here but no success.

      I get the message “Packet needs to be fragmented but DF set” When I set mtu=1465 and “Request Time Out” for any value less than 1465. (I tried 20 random values <= 1464)

      I am using wireless connection and cant figure out how to solve this.

      I noticed that "netash" works with both IPv4 and IPv6.

      Please help.

      Thanks

      By Charmis on Sep 15, 2010

    18. @Charmis, That doesn’t sound like a MTU issue, which tend to be very black and white. I would recommend you post your problem on superuser.com giving as much information as possible, including the name and URL of the website.

      By Richard Slater on Sep 16, 2010

    19. Hey Rich first of all thank you for the post, it would be really nice if you could try to help me, I’m from France but everything is exactly the same, I’ve done everything right and when I try the last step, then I get something like ” element unfounded ” do you have any idea why?

      By Allan on Sep 17, 2010

    20. Hey Allan,

      Can you try the following command:

      netsh interface ipv4 show subinterfaces

      It should print a list of subinterfaces can you paste those in here, I suspect “Local Area Connection” doesn’t translate in your culture.

      By Richard Slater on Sep 17, 2010

    21. I have a question for you. I am a somewhat experienced network and IT professional. I am fine with production networks, but am having trouble with my home network. I tried changing the MTU size on both my computer and my router, and still cannot seem to access some websites, and my network connection is slower than it should be. Do you have any other suggestions?

      BTW, my MTU size is 1500, and I can hit the website at 1472 MTU and lower, but not MTU 1473 or higher, with do not fragment set.

      By Derek on Sep 21, 2010

    22. To clarify, when you MTU is set to 1472 there are still websites you can’t access?

      You could check your:
      c:\Windows\System32\drivers\etc\hosts

      File to see if anything has maliciously added something to that file. If you connect another computer to your network does it exhibit the same issues as your computer. Try to work out if it is an issue with your computer or the network.

      By Richard Slater on Sep 21, 2010

    23. Great article,
      thanx! Where does the 28 to add come from? It gave me exactly the number, my router recommended…

      By Micha on Sep 30, 2010

    24. 20 bytes are required by the IP Header, and 8 bytes are required by the ping command (technically the ICMP Echo request).

      By Richard Slater on Sep 30, 2010

    25. Hi

      Im using windows 7+ pppoe. I see two interfaces (my connection´s name and the local area network thingy)… help me!

      By Mr Bunny on Oct 2, 2010

    26. @Mr Bunny – how do you connect to the internet? through a USB modem or through a router?

      By Richard Slater on Oct 2, 2010

    27. USB modem (directly, with ethernet cable)

      By Mr Bunny on Oct 2, 2010

    28. direct to the point. It worked fine in W7 x64 for my pppoe connection. Great! Thank you so much!!!

      By Jorge on Oct 3, 2010

    29. :D

      By Mr Bunny on Oct 3, 2010

    30. Tried this technique and worked fine up to the point of finding the valid MTU value but the 3rd step failed. I got a message saying I needed to go to administrator level, but I was logged in as the Administrator user so not clear how to move forward and apply the fix?

      By Graeme on Oct 6, 2010

    31. In Vista and Windows 7 applications don’t automatically get administrator privilege, they either need to request it or the user needs to explicitly start the application as an Administrator. The way to do this with the Command Prompt is as follows:

      1. Press the “Start” button.
      2. Type “Command”.
      3. “Command Prompt” will be shown in the search results.
      4. Right Click “Command Prompt” and select “Run as Administrator” (it will have a blue and yellow shield beside it).
      5. When prompted click “Yes” to allow Command Prompt to start as Administrator.

      You will know it has worked because the title bar will start with “Administrator:”, hope that helps.

      By Richard Slater on Oct 7, 2010

    32. What is the default mtu for the Loopback Pseudo-Interface 1. I somehow set it to 1300. Not sure if there are any detrimental effects but would like to set it to default if I can.

      By Jon Baum on Oct 14, 2010

    33. Hello Jon, I suspect it will be 4,294,967,295 for you. Which is either a “magic number” for unlimited or the highest possible number that can be stored in an unsigned 32-bit integer.

      By Richard Slater on Oct 16, 2010

    34. Thanks Richard, I always forget about this and yet again had a new machine (my first Win7 this time) not able to browse all websites (eg http://www.google.com worked and http://www.mcafee.com didn’t, well it redirected, then stopped). The above commands worked fine btw.

      But, what I don’t understand is if this problem of routers not passing ICMP properly then why don’t a vast number of people don’t get the problem, rather than apparently a few (else there would be bigger coverage I think). I wonder if it my home router that is at fault (a Cisco SOHO 97). Just wondering if you have any background insight.
      One point perhaps to add to yor above explanation is that it may be worth checking that the value in use before you start experimenting is not already low, like 1400, because my tests indicate the ping command will then fail with values above 1372, and you could end up setting the value succesively lower, but not actually fixing whatever other problem you may have! So maybe best to set to 1500 before starting, and then not testing any values above 1500-28?

      And since I’m writing, and you haven’t got bored reading this, maybe you can throw someinsight onto a similar but different problem whereby uploads and download to some site just give up partway through. For instance I can downloada 10MB test file off one site, but another site will get to say 4.xMB then stop (where this same position is a common, but not the only, stopping point). Sometimes it restarts, and if I’m using FF I can use the pause/restart download control to jiggle it to the end, but with downloads controlled directly by a program (with no pause/restart) there is often no way to force it to continue. This happens on wired as well as wireless and even in Safe Mode. Any suggestions would be much appreciated.

      By Dave on Oct 29, 2010

    35. Hello Dave,

      I am not sure why everyone doesn’t suffer from these issues. Possibly it is due to the software that is distributed for Broadband connections “fixing” it before the user ever uses a web browser.

      If your router has decent logging, I would recommend checking to make sure the connection isn’t dropping for a few seconds fairly regularly.

      By Richard Slater on Oct 31, 2010

    36. Hi
      Thanks, and just to say that having tried a spare, the upload/download problem seems to be localised to the router, must be getting old or something, but nevertheless an odd “partial failure” problem that was difficult to isolate.

      By Dave on Nov 8, 2010

    37. Hi,

      I am trying to connect my xbox to play games online through my 3g dongle which is plugged into my laptop. The xbox says MTU settings require a minimum MTU setting of 1364. I have tried ‘pinging’ the website mentioned above and all numbers i have tried come back with ‘OK’… Although the maximum number I have tried is 65000 (maximum allowed – which still comes back as “OK”!!)

      Please help! Please let me know if you need more information….

      Thanks

      By Matthew on Dec 10, 2010

    38. I have neither a Xbox or a 3G dongle, can I suggest you ask your question on http://superuser.com/

      By Richard Slater on Dec 11, 2010

    39. i did this to change the MTU for xbox live but it didn’t work. CMD said the requested operation requires elevation (run as administrator) but I am the admin

      By bernardG on Dec 27, 2010

    40. Richard

      I’m a novice at computers and I was getting totally frustrated with my hotmail not working with windows 7- until i stumbled across your explanation of the process. i needed to go down to 1464 but i finally got things going. Thank you so much from one very happy lady.

      By liz seager on Dec 28, 2010

    41. You will need to run CMD as an Administrator.

      By Richard Slater on Dec 29, 2010

    42. There is a spelling mistake in your article: “…however if it dos affect you…” should be DOES not DOS. Also, a few people made the same mistake in their comments. It’s not DOE’S, it’s DOES!!!

      -Jamie M.

      By Jamie M. on Jan 3, 2011

    43. Richard,

      Apologize that I contact you by giving a comment on a different subject.
      In ‘superuser’ you have given answer on a question about getting an ACER Aspire 5102WLMI with 4GB of memory up and running beyond POST. I have exactly that problem, but don’t get it resolved despite your answer. I have made a photograph of the PCB tracks under the DIMMs. Would you please be so kind to give me a clue what to do (referring to that picture)? Can you please let me know where to send the photograph? Thank you very much in advance!

      Hub Lemeer
      The Netherlands
      hub@lemeertjes.com

      By Hub Lemeer on Jan 10, 2011

    44. @Hub Lemeer: My suggestion would be to post on Super User… that way I and many other computer enthusiasts will see the post.

      By Richard Slater on Jan 10, 2011

    45. Hi Richard,

      I used to have this problem as well but now it is fixed (thanks to this guide). Now my other problem is computers connecting to the internet through wireless (laptops, cellphones, etc.) can’t surf the net (only google).

      my question is, do i have to set the same MTU value of the router as my computer? (in this case, the MTU value of my PC is 1400)

      additional information – i connect to the internet through my router (Belkin Double N+ Wireless Router).

      thanks in advance!

      By Eizyark on Jan 12, 2011

    46. @Eizyark,

      Possibly… in theory you should be able to set the MTU on your router, some routers also allow you to set the MTU to be sent out via DHCP. However I have never got it to work on my Linksys router. Sorry I couldn’t be any more help, if you find a solution please post it up your future comments will be automatically approved.

      Richard

      By Richard Slater on Jan 12, 2011

    47. Thanx!It help me.My MTU is 576

      By Alex on Jan 31, 2011

    48. Hi Richard,
      I am running Window 7 64bit. I recently installed XP Mode in an attempt to use the Cisco 32bit VPN. (I never did get it to work it connects but I can’t bridge between 64bit programs and after running it I can no longer connect to my router) Anyway that’s a different subject, I am now experiencing very slow file transfers. Network drive to my PC as well as to/from USB drives. Have you heard of similiar occurences?
      Thanks,
      Richard

      By Richard De Rocco on Feb 1, 2011

    49. Hi Richard,

      I have one Windows 7 machine and one XP machine. I have a NetGear WNDR3700 (or, rather, N600 — the new name for the same model). Ethernet over PPPoE. All seems to work fine except transferring large files between the two computers, which usually fails. NetGear business-level tech support said they’ve solved this by lowering the MTU.

      Usning ping tests on DSL Reports and in your suggestions, it’s clear I need to be at 1492. Using your steps, it’s clear that I’m currently at 1500 on the Windows 7 machine. I don’t yet know where I cam on the XP machine.

      Do you agree that lower the MTU is a reasonable step to take for solving the file transfer issue between the two machines?

      If so, out of curiosity, what does your fix modify (just in case I want to put it back)?

      And have you found anything newer on how to find and change the MTU in XP?

      Thanks!

      By Jay on Feb 2, 2011

    50. Hi Richard and Jay,

      I can’t see how it would affect transfers to and from USB Drives, that doesn’t make very much sense. Transfers across a network would indeed be impacted by reducing the MTU… in effect you are reducing the efficiency of network traffic as the TCP/IP stack is slicing the data up into smaller packets, each of these packets still needs to be labelled with where it is going these labels take up a fixed amount of space, so by reducing the MTU you only reduce the amount of space left in the packet for data.

      @Jay as to your specific problem, if the shoe fits… if it solves the problem and has minimal side effects the do it. You can adjust your MTU in XP with DrTCP (available from DSL Reports). You can use any value up to 1500 with the same method I described above.

      By Richard Slater on Feb 3, 2011

    51. I tried your suggestion, but I keep getting “Element not found”o matter what setting I use.
      Can this be fixed?

      By Gary N. on Feb 5, 2011

    52. Not sure, can I suggest you post on http://superuser.com/

      By Richard Slater on Feb 5, 2011

    53. Yes – thanks, spot on fix.

      One thing, you say “The host name should be a site you can not reach” where you actually mean pick a host you have problems reaching – ie. don’t use some made up name that doesnt exist and therfore cannot reach as it will obviously never work!!

      Please reword that sentance as its confusing some.

      By Al on Feb 15, 2011

    54. Hi !

      Thanks for the tip!

      I’m just having a little problem.. When I type, say ping google.com -t -l 1400, the number of bytes I send is 1400 (compared to the usual 32 that I have). After having found my MTU and set it with your command, when I simply type ping google.com, it shows 32 bytes sent, and not my MTU that I set earlier.. Is it normal ?

      Thanks :)

      (Oh, and my situation is a bit awkward, my PC is connected with Eth to a Wireless bridge and I know wireless allows greater MTU..)

      By Andy on Mar 8, 2011

    55. I am having the same Windows 7 issue as everyone else. My wireless router is detected (Belkin G Wireless) but the yellow triangle appears and says “No Internet Access.” However, a different laptop using Vista Basic has no such issues using the same router and the internet runs normally.

      When I tried your “ping http://www.yahoo.com -f -l 1472″ I get the following error message: “Ping request could not find host http://www.yahoo.com. Please check the name and try again.” This occurs even when I reduce the number as low as 1000. It seems as if it can’t even attempt the ping becuase of the lack of an Internet connection, but that is what I am trying to fix!

      This is a brand new computer and it does not even have Office loaded. It was working fine earlier and then it stopped. Nothing was downloaded or automatically updated, so I don’t know what would have triggered it. It just happened when it came out of sleep mode and no amount of reboots have worked.

      Any help would be greatly appreciated!

      By Richard on Mar 22, 2011

    56. Hi Richard,

      Sounds like you have bigger problems than this article describes, can I suggest you post your problem on SuperUser your question will be seen by many more expert users than the comments of this blog post. I would suggest you post the above information plus some further information about your environment, including the output from the command `ipconfig /all`.

      Hope That Helps,
      Richard

      By Richard Slater on Mar 22, 2011

    57. Thanks Richard – I kept getting kicked off an online game I was playing – changing the MTU solved the problem.

      I thank you, my widow doesn’t :)

      B

      By Brent on Mar 22, 2011

    58. talktalk engineer directed me to your site in order set the mtu in my laptop as at his end, it was showing as 1563 where as my router was showing the correct value of 1432. Any suggestions.

      By Tom on Mar 24, 2011

    59. For those putting the http:// in the ping command, drop that.

      ping http://www.site.com -f -l 1492

      -ec

      By Edison Carter on Apr 5, 2011

    60. I see what is going on…this web site keeps adding the http…

      ping site.without.com -f -l 1492

      By Edison Carter on Apr 5, 2011

    61. Glad I found your website through Google Search. Instructions were clear, and helped me get the MTU set on my Mom’s PPPoE DSL connected PC.

      Your contribution to the knowledge base on the internet is greatly appreciated.

      Thanks!

      By Tim Raymer on Apr 9, 2011

    62. Thanks for helping us all out! The above change works well (1472 for ping), but I can’t quite understand. I have a computer attached to a wireless router. The router is also connected to a NAS drive. All three have their own MTU default. Should the NAS drive MTU be reduced the same way as the PC? Should all three be the same MTU value?

      By Ken on Apr 13, 2011

    63. If a device needs to connect to the internet via your broadband link then it will need to have it’s MTU updated, if it is only going to be used locally you can leave it at the default.

      By Richard Slater on Apr 13, 2011

    64. Richard – many thanks for this. I can now listen wirelessly to my NAS-stored music on my hi-fi! The required MTU for my Netgear ReadyNAS Duo is 1430.

      By Roy Simpson on Jul 26, 2011

    65. Thanks so much for the info, I normally use something like dr tcp but this wouldn’t work. Thanks again

      By James on Aug 15, 2011

    66. Hi, I have problem with upload. After changing of MTU – donwload is little bit faster and its great. from 7MB to 9MB (max. speed). But upload is still same about 2,5MB. This is happening only with windows. When i try upload with linux on the same network it is 9/9MB in both directions. I have to say that is not problem of the local network but i have wifi-n reserved connection to the gateway and problem with upload is only via wifi. So please can you help me what is wrong settings in windows? Thanks

      By krynn on Sep 16, 2011

    67. Hi krynn,

      I don’t know personally, can I suggest that you post your question up on http://superuser.com/. Explain your problem clearly as you have in your comment then thousands of geeks like me will see it!

      All the best

      By Richard Slater on Sep 17, 2011

    68. Altering the MTU setting solved problems I have had for months – couldn’t access certain sites and itunes always timed out

      noted a comment re my wireless router having an MTU limit of 1400

      reset the pc and BINGO !

      Can’t believe it was so simple

      Thanks for the helpful advice

      By YorkieSteve on Oct 5, 2011

    69. I have done everything,but when I try to set it says “this operation requires elevation” What does this mean?

      By Travis on Oct 6, 2011

    70. You need to run the command prompt as an administrator.

      By Richard Slater on Oct 8, 2011

    71. Thank you thank you thank.

      I had a brand new PC straight out of the box failing to get internet connectivity on 99% of sites, and got nothing from Microsoft except rote “have you tried the troubleshooting function” and “it must be your ethernet connection.”

      The MTU was set to high by just 12. Fixed it, and now things are working great. Thanks again.

      By Windows7Starter on Oct 22, 2011

    72. I’m trying to connect to an apache web server on my own network from a Windows7 netbook and your info is very helpful in pinning down where the problem lies. The Apache system is directly ether connected to the router.

      Other systems work fine. All works ok if the netbook is connected via ether cable but not via wifi. The MTU for both connections is shown as 1500.

      With the netbook ether connected the ping gives ok for 1472 and below, and ‘needs to be fragmented’ is 1473 and above just as your article describes. All consistent with MTU of 1500.

      With wifi though I get ping ok for 1468 and below, ‘need to fragment’ for 1473 and up. The area between ie 1469 to 1472 inclusive gives timeout.

      If I ping the router from W7 + wifi it gives a clean split at 1472/3.

      If I ping from the ubuntu box (using linux ping) the other way I get exactly the same symptoms.

      Can anyone shed light on this ‘gap’ and why it does not show whwn pinging the router?

      regards
      Phil

      By Phil Brady on Oct 25, 2011

    73. Hey, I have two questions, first that is a -L right after -f right? and second when I ping the website, it says request timed out everytime, help please!

      By Mikey Romar on Nov 4, 2011

    74. Hey Richard,

      I followed the directions in your well-written article to fix my mother-in-law’s Internet. She emitted a happy cheer when the lottery website finally opened for her. Thank you!

      Cheers,
      Ryan

      By Ryan on Nov 14, 2011

    75. yep, thats l for lemur. If it says request time out then the site is unreachable, your problem is something additional or perhaps other than a MTU issue.

      By Richard Slater on Nov 14, 2011

    76. Thanks it worked on windows 7
      i kept lowering mtu size within my pppoe connection till i tuned to 1350 and it works

      By sami on Nov 21, 2011

    77. Does this process work if you are behind a router (router’s MTU is currently set to manual/1492)? and if the value I got was 1372 do I need to set this for all windows machines AND the router itself?

      By Johnathan on Dec 13, 2011

    78. yes, it works if you are behind a router.

      By Richard Slater on Dec 14, 2011

    79. tooo good iformation…i am so much impressed… thank u so very much…

      By anonymous on Jan 6, 2012

    80. Thank you SO much – I was looking everywhere for simple solution for my problem that didn’t involve downloading other programs! This worked perfectly!

      By Christine on Jan 14, 2012

    81. Hi Richard
      Thanks for the advice it helped me when trying to connect to my Asus O!play on my LAN to allow media sharing, one point I had the same difficulty that some of the other posters had with – element not found – but solved it, I was typing “Local Area Connection” when I should have been typing “Local Area Connection 2″ -hope this helps

      By Simon on Feb 16, 2012

    82. I use the German version of Windows 7. Should I use “LAN-Verbindung” instead of “Local Area Connection” for setting the MTU or must I still use the English version. I have also found another version of the command with “1″:
      “netsh interface ipv4 set subinterface “1″ mtu=1452 store=persistent”. My current MTU setting is:

      MTU Medienerkennungsstatus Bytes eingehend Bytes ausgehend
      Schnittstelle

      ------ --------------- --------- --------- -------------
      4294967295 1 0 119610 Loopback
      Pseudo-Interface 1
      1500 1 12009855 2024867 LAN-Verbindung

      By John B. on Mar 4, 2012

    83. Just replace “Local Area Connection” in my command with “LAN-Verbindung”. Unless I am mistaken “LAN-Verbindung” translates to English as “LAN-Connection” which technically is a better description of what it is.

      With regards to the alternate version of your command; you don’t actually need an exact match for a subinterface name, so using “1″ would match a subinterface if it was the only one containing a “1″. In your example it would match the Loopback Interface, changing the MTU of which I would not recommend.

      By Richard Slater on Mar 4, 2012

    84. Thanks, I have tried it with “LAN-Verbindung” and it works. I have tested another command: “netsh.exe interface ipv4 show interfaces” and get this overview:

      Idx Met MTU State Name
      --- ---------- ---------- ------------ ---------------------------
      1 50 4294967295 connected Loopback Pseudo-Interface 1
      10 20 1452 connected LAN-Verbindung

      Then the command “netsh interface ipv4 set subinterface “10″ mtu=1452 store=persistent” would make the same change.

      By John B. on Mar 4, 2012

    85. If I have 2 wireless WIfo routers, I still only see one “Wireless Network Connection”. How do i set both?

      By Tom on Mar 7, 2012

    86. Hi Tom,

      The change is made to the network adapter (i.e. “Wireless Network Connection”) this adapter will be used for connecting to all WiFi hotspots. It is possible that the two Wireless Access Points will require different MTUs, in which case you will need to select the lower of the two.

      By Richard Slater on Mar 7, 2012

    87. Very good info. I heard yesterday about my company’s VPN, Cisco Anywhere, had a problem with the MTU size. I used your info to double-check my setting on my Windows 7 laptop. They pre-set the MTU size to 1200 for the VPN connection. Your info was right on target for me. Thanks…

      By Larry McAlpin on Mar 9, 2012

    88. well i did the ping http://www.actuaries.org.uk -f -l 1472

      and here is the result ? Now how i’m able to set my MTU (STEP 3) ?

      Pinging http://www.actuaries.org.uk [94.236.82.166] with 1472 bytes of data:
      Reply from 94.236.82.166: bytes=1472 time=131ms TTL=108
      Reply from 94.236.82.166: bytes=1472 time=123ms TTL=108
      Reply from 94.236.82.166: bytes=1472 time=116ms TTL=108
      Reply from 94.236.82.166: bytes=1472 time=121ms TTL=108

      Ping statistics for 94.236.82.166:
      Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
      Approximate round trip times in milli-seconds:
      Minimum = 116ms, Maximum = 131ms, Average = 122ms

      By Ely on May 29, 2012

    89. Thanks ! It work for me exactly as you say !

      By jorj on May 29, 2012

    90. Thanks for this post. Even though it’s 3 years old, it still works. Allowed me to get on the Internet through my VPN. Marvellous!

      By Michael Horne on May 31, 2012

    91. Hello Richard,

      thanks for the post. May I ask if you can connect in this site? www2.pse.com.ph. Its another website of http://www.pse.com.ph or the Philippine Stock Exchange.
      I can ping it but I can’t browse it. :(

      Thanks,

      Renzie

      By Renzie on Jun 5, 2012

    92. Richard,

      I found an alternative website. thank you.:)

      Renzie

      By Renzie on Jun 6, 2012

    93. i used this method and successfully changed my MTU, thanks so much!
      but i have a related question. every time i reboot or shut my computer down and boot it up again later, the MTU settings i adjusted are lost :(
      i’m running cmd.exe as administrator and using store=persistent at the end of the command line, but still it keeps resetting itself to MTU=1300 after every (re)boot.

      is there anything i can do to save this setting ?

      By Matt on Jun 25, 2012

    94. Works for me. Thank you very much!

      By little daddy on Jul 7, 2012

    95. Great article – thanks. Issue for me though is…
      > default router (Belkin) mtu = 1454
      > laptop; Win7; wireless connection
      > ran the ping test: frag cleared at 1420
      > changed mtu (on the laptop) to 1420
      ping (same site) now fragments???
      ping using mtu 1454… still fragments???
      > changed mtu on the router to 1420
      ping still fragments

      Did the same with a hard-wired connection, same results – looking at this because of outlook/internet transport delays

      By SteveG on Jul 31, 2012

    96. Thanks for this post. I have a pc running windows 7 at 1500 mtu, a pc running xp, but hooked up to a remote server via vpn and both are connected to the modem via linksys E4200 router. I understand vpn default mtu setting is 1400. I have now lowered the mtu settings for both the router as well as win7 pc to match this. But when pinging at 1400, I do see frags, but when I lower it to 1372, dont see any frags. My web browsing is very fast, but I also have a Vonage voip hooked up to the router. Will the frags at 1400 mtu cause problems on voip resulting in poor voice quality? thanks for your help

      By maka thuka on Aug 16, 2012

    97. subsequent to my earlier post, the setting of 1400 MTU, my iPad cannot connect to internet. I went back up to 1462 and the iPad is working fine. But on pinging the frag issue remains, which also is seen in voip quality and slower page loading on win 7 pc. Just cant win. Help will be highly appreciated

      By maka thuka on Aug 16, 2012

    98. I followed the instructions on this, but every time I set the mtu to a new value, I do a test ping and it times out. I am constantly lowering it until I get a successful ping, but once I set it again, its useless again. I can’t get to google and I know if I change the router mtu I can get it to work, but the X-box requires a min value of 1436 or some such. Please help.

      By FWT on Aug 28, 2012

    99. Oh and I forgot to add, the laptop in question works fine on other networks.

      By FWT on Aug 28, 2012

    100. Thank you Richard. This solved my Error 10053 instantly. Fantastic tutorial man. (Win7-HomePre64)

      By Donny on Sep 5, 2012

    101. Hi Richard,

      My problem is back again. It was fine yesterday after I changed the MTU. I tried to do the same thing, but it didn’t work. Any help is appreciated.

      By Donny on Sep 6, 2012

    102. ive tried this n wont work to be honestdont have a clue ive read up on loads of thing about it i just cant get face bookto load but every other program will help

      By laura on Nov 16, 2012

    103. thanks man,that was that much helpful !

      By prabaharan on Dec 23, 2012

    104. Hello!

      I found out that my ideal MTU is 1500… and that just doesn’t make any sense to me because it seems that everyone has to lower theirs to some degree. I get to leave mine at its current setting? The default setting? My ideal is really the default? My head hurts.

      By Alec on Jan 17, 2013

    105. 1500 is perfect, that simply means that there is nothing in between you and the sites you are trying to connect to that need a smaller MTU. It is in fact the way it should be, alas it’s not a perfect world for the rest of us.

      By Richard Slater on Jan 17, 2013

    106. the following link gives another way of achieving same – by editing registry…

      http://www.windowsreference.com/windows-2000/how-to-manually-set-the-mtu-size-in-windows-xp-2003-2000-vista/

      By Shekky on Jan 29, 2013

    107. Hi

      I’ve followed all your very clear instructions and managed to find out that the MTU needs to be 1458 but I don’t know which of figures I need to change because I get 3 interfaces as well as the default one. They are:

      Wireless Network Connection
      Local Area Connection
      Wireless Network Connection 2

      I’m not sure whether I should change them all or not.

      I’ve tried changing both wireless networks but it hasn’t worked.

      I know that the problem lies with my new machine as my previous one and another currently in use is working fine.

      Any help much appreciated.

      Many thanks

      By Gill on Mar 21, 2013

    108. Richard,

      Thank you, thank you, thank you! You’re the man. I was dealing with the same issue you were and nothing I did worked. I did basically the same things you did and zero. I knew it was a Windows issue because I installed Linux Ubuntu side by side and had no problems with the net. I let it go for a couple of weeks and a voice popped into my head this morning to search for the answer again. I did and your fix was the first one that popped up! All is fine again, thanks again!

      By Alex on Mar 23, 2013

    109. Thanks a ton!! I had been using this wifi hotsopt since last 2-3 months, but it was not giving enough speed to download on my android. But your solution worked like a charm!! Again Thanks a lot..

      By Vaibhav Natekar on Mar 30, 2013

    110. there is a hyper-v host with a single windows 7 .VHD that can be accessed multiple times concurrently. how can I set globally? as I get a 4 or 7 at the end of my connection?

      By Chris Frenzel on Apr 20, 2013

    111. I am facing the problem of invalid ip config. while using LAN wire but my wifi works fine.
      So i tried using the technique mentioned above to fix the problem.
      When I have tried pinging http://www.google.com, it keeps showing that the host name couldn’t be found!

      How do i fix this thing.. any help ?

      By Shubham on Apr 28, 2013

    112. Also, with regard to my last inquiry, i would like to mention that with the same wired connection I am able to connect to a different internet by changing the ipv4 and proxy settings using the same LAN port.
      This problem started to happen only after I installed ‘Connectify’ used to create wi-fi hotspot.
      Initially i was able to access the same internet connection with the same port without any problem and was able to switch between the two proxies and ipv4 connection settings.

      By Shubham on Apr 28, 2013

    113. I had a problem yesterday where suddenly I could only access Google search and the search pages of eBay. If I tried to access one of the sites a Google search listed, or if I tried to do something else on eBay like place a bid, I got a “Firefox cannot find the server at …” error. When this had lasted most of the day, I switched off everything, including the router/modem, for a couple of hours, and then things worked ok again. I’m using a new TPLink modem on BT Broadband and I thought it probably was something to do with the modem, but if it happens again, would an MTU change be a more permanent fix?

      By Phil on Apr 28, 2013

    114. are you pinging http://www.google.com?, for example:

      ping -l 1472 -f http://google.com

      this would be incorrect as you are specifying the scheme (protocol, i.e. http), the correct command is:

      ping -l 1472 -f google.com

      By Richard Slater on Apr 28, 2013

    115. I would suggest it is unlikely, MTU issues in my experience have always been all or nothing.

      By Richard Slater on Apr 28, 2013

    116. Hi.
      In the final step the procedure failed and showed that “element not found” !!
      what does that mean????

      By sunnyD on May 18, 2013

    117. what was the exact command you used?

      By Richard Slater on May 18, 2013

    118. This really helped. I was not able to access certain sites like yahoo.com, microsoft.com on my Windows 7. Thanks for sharing this information.

      By Gargi on May 28, 2013

    119. Error 101 (net::ERR_CONNECTION_RESET): The connection was reset. I have changed mtu but still can’t access facebook page and when I am pinging http://www.facebook.com it shows
      packet needs to be fragmented but DF set.
      (4 times)
      packet stastics
      packets: sent=4, recevied=0, lost=4(100% loss)

      By priyanka on Jun 1, 2013

    120. “Element not Found”

      Microsoft Windows [Version 6.2.9200]
      (c) 2012 Microsoft Corporation. All rights reserved.

      C:\WINDOWS\system32>netsh interface ipv4 set subinterface “Local Area Connection
      ” mtu=1492 store=persistent
      Element not found.

      C:\WINDOWS\system32>netsh interface ipv4 set subinterface “wireless Network Conn
      ection” mtu=1492 store=persistent
      The filename, directory name, or volume label syntax is incorrect.

      C:\WINDOWS\system32>ping http://www.cantreachhissite.com -f -l 1464

      Pinging http://www.cantreachhissite.com [199.101.28.20] with 1464 bytes of data:
      Reply from 199.101.28.20: bytes=1464 time=200ms TTL=57
      Reply from 199.101.28.20: bytes=1464 time=187ms TTL=57
      Reply from 199.101.28.20: bytes=1464 time=95ms TTL=57
      Reply from 199.101.28.20: bytes=1464 time=123ms TTL=57

      Ping statistics for 199.101.28.20:
      Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
      Approximate round trip times in milli-seconds:
      Minimum = 95ms, Maximum = 200ms, Average = 151ms

      C:\WINDOWS\system32>netsh interface ipv4 set subinterface “Local Area Connection
      ” mtu=1492 store=persistent
      Element not found.

      C:\WINDOWS\system32>netsh interface ipv4 show subinterfaces

      MTU MediaSenseState Bytes In Bytes Out Interface
      —— ————— ——— ——— ————-
      4294967295 1 0 1043600 Loopback Pseudo-Interface 1
      1500 2 4577841 362517 Wi-Fi
      1500 5 0 103320 Local Area Connection* 11
      1500 1 342157502 16746163 Ethernet

      C:\WINDOWS\system32>

      By lily k on Jul 2, 2013

    121. Hi Richard,

      Excelent article!, I was going crazy! until I reach your site.

      I just have a question. I´m facing this issue when we try to access a tomcat server (installed on a windows 7 box) from another lan (connected to server windows 7 box via lan to lan through satellite link).
      I need to stablish mtu in windows 7 box too(where I have the tomcat installed) ?
      thanks,
      Walter

      By Walter on Jul 11, 2013

    122. Thanks a ton Richard , this really helped . Had this problem for months finally found the solution here . Kudos !!!!

      By Kat on Aug 29, 2013

    123. Hello guys, I have a question. My mtu value is 1500, so it says that about “packet needs to be gragmented…” so i look for a lower value, and found where the msg doesnt show anymore. But when i Set it to that Value, and ping with the working value, it appears again, and now the working value is the same -28, and so on…
      Any ideas?

      By Luis on Sep 1, 2013

    124. Because every packet has an overhead over the size of the packet, Wikipedia has a good diagram to help visualize this overhead.

      By Richard Slater on Sep 1, 2013

    125. Thank you for your reply, but I really don’t know what to do with that. I don’t know much about networks. Any idea what can cause this? because I can browse any site when i restart my pc, but after a while the error starts to pop up in every site. I clear the cache, but that’s not working. Thank you for your time.

      By Luis on Sep 2, 2013

    126. So far I tried:
      1) reset my hosts file.
      2) Change mtu.
      3) I’ve checked and I’m not using any proxy.

      I was thinking about reinstall my antivirus, since in one forum i saw a guy who had this issue and had to reinstall his Avast antivirus to make it work again. But if any of you have an idea, would be useful.

      By Luis on Sep 9, 2013

    127. Hello Rechard,
      Everything works well for me till third step.
      But in the third step i got an error that Element not found.What to do?Please help…!!

      By Ketul on Sep 28, 2013

    128. What’s Going down i’m new to this, I stumbled upon this I’ve found It absolutely useful and it has helped me out loads.
      I hope to give a contribution & assist other users like its aided
      me. Great job.

      By Top infomercial production companies Los Angeles on Oct 12, 2013

    129. I also got the element not found on the third step windows 8.1 64 bit, PPOE, DSL, Router

      By Bill on Nov 2, 2013

    130. Thanks for a very informative explanation and straightforward instructions.

      By jimmy on Nov 13, 2013

    131. SOLUTION TO “element not found” error

      When you run the command , “netsh interface ipv4 show subinterfaces”

      pay attention to the interface name in the column and use only this name while running the command
      “netsh interface ipv4 set subinterface “Wireless Network Connection” mtu=1458 store=persistent”

      For e.g. I was running the above command as it is but then I saw that I had named my “Wireless Network Connection” to “Wireless” some time back.
      Therefore I ran the command like this “netsh interface ipv4 set subinterface “Wireless” mtu=1458 store=persistent”

      Notice that I wrote “Wireless” in place of “Wireless Network Connection” and it worked.

      By Pooja on Nov 22, 2013

    132. It’s different under windows 8 for those with the “Element not found” error,

      You must replace the word “Local Area Connection” in the command, with the applicable “Ethernet” or “Wi-Fi”

      Hope this helps someone, spent 15 minutes trying to figure that out.

      By johndoe on Dec 4, 2013

    133. Hi,

      I’m using Win 8.1
      When I change the mtu size in cmd it changes to the value i select, but after rebooting it’s back to 1500. Somebody got an idea for me ?

      By dnl on Jan 9, 2014

    134. I am having the same issue as dnl above; I am using Win 8.1 and after changing my MTU everything works great, but once I reboot the MTU goes back to its default.

      By Robert on Feb 25, 2014

    135. Thank you Johndoe. :)

      By Maruf on Mar 7, 2014

    1. 14 Trackback(s)

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