(Note:  If you find this information useful, and it solves your problem, please leave a comment at the bottom of the post, and/or share it via the link below. Thank you.)

Have you run into the Windows Update “infinite loop from hell”?  If you have, you know what I”m talking about. You get a Windows update, it installs and requires that you reboot to finish the install. After rebooting, the second part of the install fails, and it uninstalls itself. The next time you try to install Windows updates,  the same thing happens on the same update. Repeat ad nauseum.

If you check the Windows update status, it will probably tell you that the error code is “80071aa7″, but give no further information. A search of Microsoft”s site (as of today) yields no further information, and a search of the entire Internet finds plenty of others asking how to solve it, but no one giving a solution.

Well, after 2 long evenings of fighting a Vista laptop which failed to install kb953838 (security update for IE7), I finally found a solution.

First, you need to find the exact file on which the install is failing. In order to do this, you need to examine the file “WindowsUpdate.log”, which is in the “\windows” directory, by running this command:

notepad %windir%\WindowsUpdate.log

Then, search (Ctrl-F) for the error number, including a “0x” prefix, such as “0x80071aa7″. You will find a line that looks something like this:

2008-10-06      11:29:23:890    1140    dac     Handler Post-reboot status for package Package_for_KB953838~31bf3856ad364e35~x86~~ 0x80071aa7.

followed by:

2008-10-06      11:29:23:890    1140    dac     Handler WARNING: Got extended error: “POQ       Operation       HardLinkFile    OperationData   \SystemRoot\WinSxS\x86_microsoft-windows-i..tocolimplementation_31bf3856ad364e35_6.0.6000.16711_none_fff8e71ba4b3b364\WininetPlugin.dll, \??\C:\Windows\System32\migration\WininetPlugin.dll”

The important thing to notice is the filename at the end. In this case: C:\Windows\System32\migration\WininetPlugin.dll. (Don”t worry about the “\??\” before the filename.)

I have also seen “UnlinkFile” rather than “HardLinkFile”, but the filename was the same in all cases.

If you run a disk scan on drive C: (start / run / “chkdsk c: /f”), it will give you an error on the same “WininetPlugin.dll” filename. Unfortunately, even though is says it fixed the error, it did not. If you immediately run the chkdsk command again, it will give the same error, and tell you it fixed it again.

Typically, in a case like this, I would rename the file out of the way, put another copy there, and retry the install. Unfortunately, there appears to be something “special” about the “c:\windows\system32\migration” directory and/or the “WininetPlugin.dll” file, as I was unable to rename the file out of the way, as even running as administrator, an “access denied” error is given. Even using our old friend, BartPE, the file could not be renamed and/or removed, as the same “access denied” error occurs there as well.

Fortunately, Vista includes the ability to run in a recovery mode, by pressing F8 during boot. The first menu choice will be something like “recover windows”. Don”t worry, it”s not going to ”recover” Windows by wiping the drive and reinstalling it. Rather, it will take you to a special recovery mode of Windows. After booting, you will be given a dialog box with several options. Select “command prompt”. This will open a command prompt window. Don”t worry if you”re unfamiliar with the command prompt — I”ll walk you through it.

First, you need to navigate to the directory (“folder”) in the file you got above, by using the “cd” (“change directory”) command. That is everything up to, but not including, the filename at the end. In this case:

cd /d c:\windows\system32\migration

Now, from within this special recovery mode of Windows, you have the ability to rename to file out of the way:

ren WininetPlugin.dll WininetPlugin.bad
copy WininetPlugin.bad WininetPlugin.dll

At this point, running “chkdsk” will find the same error(s) as before, but it will actually be able to fix them:

chkdsk c: /f

Note that now, if you run “chkdsk” a second time, it will not find any errors.

Finally, type “exit” to exit the command prompt window, and reboot the system. You will now be able to install the update and have it successfully complete upon rebooting.


  1. 床墊 says:

    I am so happy to read this. This is the kind of info that needs to be given and not the random misinformation that is at the other blogs. Appreciate your sharing this beneficial content.

  2. pc games 10 says:

    Super-Duper site! I am loving it!! Will come back again – taking you feeds also, Thanks.
    Hello. Great job. I did not expect this on a Wednesday. This is a great story. Thanks!

  3. Online Casino says:

    hey your blog design is very nice, clean and fresh and with updated content, make people feel peace and I always like browsing your site.

    – Thomas

  4. dental patient information in austin says:

    I am going to link my blog to this website. I believe my visitors will locate it extremely beneficial given the well written subject matter. Thanks

  5. wisconsin union theater madison wi says:

    This was a very good read by you hope to visit more really soon.

  6. Hank Hookfin says:

    bookmarked your blog thanks :)

  7. Santos Pettitt says:

    thanks for sharing!

  8. definitions of online auctions says:

    Very informative post. Thanks for taking the time to share your view with us.

  9. row boat says:

    I find myself coming to your blog more and more often to the point where my visits are almost daily now!

  10. Schedule says:

    You you should change the post subject title RunOnFriday.com Blog » Blog Archive » Windows update error 80071AA7 *solved* (re-post) to more better for your content you make. I enjoyed the the writing however.

  11. buy used car New Orleans says:

    I’ve been visiting your blog for a while now and I always find a gem in your new posts. Thanks for sharing.

  12. videos divertidos says:

    This is valuable information , thanks I will try it out!

  13. government auction Jacksonville says:

    I just book marked your blog on Digg and StumbleUpon.I enjoy reading your commentaries.

  14. noone says:

    I wish to thank you for providing this information. I’ve just learned how to use the world wide internet and am just catching up to these young whippersnappers.

  15. azul says:

    I greatly appreciate your information.
    I carefully followed your instructions and was finally able
    to solve my 80071aa7 problem and succeded in installing an update.
    Thanks again for sharing this valuable information.

  16. Alex says:

    I have the following filename that is included in the error message (from the WindowsUpdateLog):


    Can I also use your method but instead of “WininetPlugin” I enter “Bridge.sys”?

    Very sorry if I am not allowed to ask things here (not very familiar with blogs and stuff) but please help me if it’s allowed


  17. admin says:


    If the filename is in the line associated with the error, then I would expect that you could do the same thing with the “Bridge.sys” file instead. Of course, since it’s in a different directory than my WininetPlugin.dll file, you need to change the “cd” command to point to the correct location:

    cd /d c:\windows\system32\drivers
    ren Bridge.sys Bridge.bad
    copy Bridge.bad Bridge.sys

    The good thing about this fix is that it can’t cause any problems if this wasn’t the cause, because you’re not replacing that file with anything other than a copy of itself. (So you can’t, for example, replace it with the wrong version of the file.)

    Let me know if it solved your problem.

  18. Alex says:

    I think I forgot to submit my previous comment because it’s not above. I can happily inform you that I’ve managed to install Service Pack 2. I just entered the different filename and I only had a small error when it was shutting down, so I took the power away and when I restarted again it finished the update. After that I installed all the new updates that were available for SP 2.

    Thanks for your time I am very happy that this error is solved!

  19. mrguyii says:

    I cannot express in words what this information has done for me. After over a year not being able to install many updates, I would just hide them because I was unable to find a solution. This only became a major problem in the fall of 2010 when I was not able to install Internet explorer 9 beta. Now, IE9 is the norm, I have been scrambling to find a solution. Right when I was only minutes away from doing a clean re-install of Vista to address this problem, I did my final search for a solution…and found your answer. The instructions here were excellent and I only had to try it once and now all of my problems are gone. For me, this is truly a God Sent answer, His instrument being who ever posted this solution. I will be sure and pass this one along. Many thanks to the person who post this solution.

    Peoria, IL
    April 15, 2011
    Vista Home Premium

  20. admin says:

    “mrguyii”, I am glad to hear how much my solution helped you out. It’s amazing how something that sounds like a minor annoyance can cause such big problems. When I had run into it on a client’s laptop, I took it as a challenge to find the solution, as I really hate the wipe-and-reinstall approach, and only use that as a last resort.

    – Ken –

  21. abi c says:

    Thank u so much!!! I have no idea about computers and have been having this problem for ages with my updates…just today decided to google it and ur blog came up! i followed the steps and it works! yay! even microsoft were no help…so thank u so much!!!

  22. xjoua says:

    if you r still checking out this page could tell me about the “reccvery mode part because i don’t really get the step. you could mail it to my email: xjoua@yahoo.com

  23. Geo0319 says:

    Wow! A-MAZ-ING!!! Why doesn’t Microsoft or any of the other Tech Forums provide an answer like this? This was extremely detailed and helpful and it worked on the first try. I would like to add that my error msg was a bit different than the one mentioned on this blog but the solution still worked. I would also like to mention that I had 12 Window Updates to install and each one failed with a Error 80071AA7. I was able to install each of them individually (one at a time – not even 2 at a time would work)except for KB2685939. That one was a bugger. Nothing, absolutely none of the other solutions offered by other techs worked. This solution did work. I wish I would’ve found this before installing the other 11 individually. That was very time consuming. Thank you very much for this. I registered to this site and plan to use it frequently if only I can figure out how. This is very confusing to me. The only way I got to this page was to type in the full url but there is no way I could find this page from the home page. If you could help with that, I would be even more appreciative. And lastly, I plan on mentioning this blog on the forum in which I am still waiting for a reply to this problem. Hope you don’t mind. Thank you again. Your blog is vun-der-bar !!!!

  24. admin says:

    I’m glad people have found this post helpful. I, too, couldn’t find any solutions when I ran into this issue, which is why I decided to write this post in the first place.

    Xjoua: As for “recovery mode”, I mention that it’s from the F8 menu during boot. By that, I mean that you need to press F8 when Windows first starts booting. Timing is important — press it to soon, and the BIOS sees it during POST — press it too late, and Windows is already booting. I find it best to simply press F8 every second or so once you get whatever boot screen your system shows. (This is the very first screen, *before* the Windows logo appears.) At that point, you will get a menu of boot options, the first of which should be “recover Windows”.

    Geo0319: I don’t know what link you were following that failed to take you directly to this page, but if you ever have trouble finding it again, just go to the blog’s main page — http://blog.runonfriday.com — and look at the “featured articles” list on the right-hand side. You’ll find a link to this page there.

  25. I am the Pirate says:

    I’ve been having this problem for quite a while now, and finally got fed up enough to try to fix it. When I searched the WindowsUpdate.log I found several instances of the 0x80071aa7, but they all had \C:\Windows\System32\drivers\ntfs.sys as the file. Isn’t that something your computer has to have?
    Any help would be appreciated.

  26. rjm says:

    Thanks so much for this article. It’s great to not have to do a full reinstall!

Leave a Reply

You must be logged in to post a comment.