SOLVED: Cannot Install .NET 3.5 On Windows 8.1 Error 0x800F0906 and 0x800F081F

UPDATE: Dec 2016 – While the process below works very well, you can eliminate future .NET install problems by installing FEATURES ON DEMAND on your companies WSUS server.

If you are unable to install .NET 3.5 on Windows 8 or 8.1 and end up with errors like 0x800F0906 and 0x800F081F you will find that errors relate to corrupt or limited access to the source files.  In ALL of the times I have tried to get around this, the source has NOT been the issue.

Often you can just install .NET 3.5 by bringing up a CMD window (don’t forget to right click and RUN AS ADMININISTRATOR) and then type either:

Dism /online /enable-feature /featurename:NetFx3 /All /Source:<drive>:\sources\sxs /LimitAccess


DISM /Online /Enable-Feature /FeatureName:NetFx3 /All

In my most recent situation I would then error out with 0x800F081F  and the logs would show:

2014-09-10 19:07:54, Error                 DISM   DISM Package Manager: PID=5116 TID=4028 Failed finalizing changes. – CDISMPackageManager::Internal_Finalize(hr:0x800f081f)
2014-09-10 19:07:54, Error                 DISM   DISM Package Manager: PID=5116 TID=4028 The source files could not be found; their location must be specified using the /source option to restore the feature. – GetCbsErrorMsg
2014-09-10 19:07:54, Error                 DISM   DISM Package Manager: PID=5116 TID=4028 Failed processing package changes with session options – CDISMPackageManager::ProcessChangesWithOptions(hr:0x800f081f)
2014-09-10 19:07:54, Error                 DISM   DISM Package Manager: PID=5116 TID=4028 Failed ProcessChanges. – CPackageManagerCLIHandler::Private_ProcessFeatureChange(hr:0x800f081f)
2014-0910 19:07:54, Error                 DISM   DISM Package Manager: PID=5116 TID=4028 Failed while processing command enable-feature. – CPackageManagerCLIHandler::ExecuteCmdLine(hr:0x800f081f)


If this is your case, then .NET may have been patched on your machine… but wait, you say, it is not installed so how could it be patched… that is a good question.  If you look at your WINDOWS UPDATES > HISTORY, you may see some .NET 3.5 patches that have been installed.  If that is the case go to PROGRAMS AND FEATURES > VIEW INSTALLED UPDATES (from the menu on the top left) and find them by KB number.  Note that I have found the names of the patches Windows Update History do NOT match what is in INSTALLED UPDATES… go figure.

Specifically I suggest you look for (and uninstall) KB2966826 & KB2966828 .  In my most recent case I only found KB2966828 but after I uninstalled it and rebooted (yes, the reboot was necessary)  I could install .NEt3.5 on my Win8 PC.

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  1. sodiq October 24, 2017 at 10:57 am

    have problem with .net framework error code 0x800f922

  2. David Nguyen July 13, 2017 at 1:30 pm

    I had the same issue on Windows 10. I found some articles that said to place a copy of Windows 10 on my local drive and then use command line to reinstall .NET 3.5. Here is the command I used below. You will have to change the a path if you place your Windows 10 folder somewhere else other than C:\

    C:\WINDOWS\system32>DISM.EXE /Online /Add-Capability /CapabilityName:NetFx3~~~~ /Source:C:\Windows10\sources\sxs

    Deployment Image Servicing and Management tool
    Version: 10.0.15063.0

    Image Version: 10.0.15063.0

    The operation completed successfully.


  3. Prateek January 3, 2017 at 7:07 am

    I don’t have the KB2966826 & KB2966828 updates. What should I do?

  4. Shahrukh Parvez January 14, 2016 at 12:20 pm

    Please help still i getting an errors installing .Net 3.5. I have tried all solutions.

    the referenced assembly is not installed on your system

    Error code: 0x800736b3

    Please help me to install

    • Ian Matthews
      Ian Matthews January 25, 2016 at 9:37 pm

      What error / message do you receive when you try to install it from the disk using the Dism /online /enable-feature /featurename:NetFx3 /All /Source::\sources\sxs /LimitAccess command?

      • Cristina Corrales May 2, 2017 at 2:22 pm

        I have the same issue, I can’t install .net framework for IIS in Windows server 2012 R2 but I don’t have installed KB2966826 & KB2966828.

        When I execute the Dism /online /enable-feature /featurename:NetFx3 /All /Source::\sources\sxs /LimitAccess command I received the Error: 0x800f081f

        And in the log it says: Failed while processing command enable-feature

        What else I can do? 🙁

        • Ian Matthews
          Ian Matthews May 24, 2017 at 4:51 pm

          I see that what you typed in included TWO colons after /SOURCE . Did you put the drive letter in? For Example, assuming your DVD is in D:

          Dism /online /enable-feature /featurename:NetFx3 /All /Source:d:\sources\sxs /LimitAccess
          alternately it can pull the files from the web using
          DISM /Online /Enable-Feature /FeatureName:NetFx3 /All

          Also, make sure you have RIGHT clicked on CMD.EXE and selected RUN AS ADMINISTRATOR

  5. Lenny Ankireddi September 4, 2015 at 7:28 am

    Thank you! Found the Security Update KB2966828 installed and removed it. Worked like a charm on retry.

  6. Frank August 28, 2015 at 4:40 am

    Hi. im having similar issues on my windows 10. error code 0x800F081F while trying to install .net 3.5. there are no kb installed updates. none @ all, yet none of these solutions has worked for me. please i need a help and a solution asap

    • Ian Matthews
      Ian Matthews December 27, 2015 at 4:43 pm

      I just had the same problem on Windows 10 myself and found this fix of using DISM to pull the files from the DVD to work without problem. I know this does not solve your Windows 10 issue, but I can say that it did work. I would try again and let us know how it goes.

  7. vikrant August 21, 2015 at 10:35 am

    i have recently install a window and i have tried all the above thing but still failing to download the framework

    • Ian Matthews
      Ian Matthews December 27, 2015 at 4:44 pm

      Last week I used the DISM solution to solve this issue on Windows 10.

  8. Sims01 July 8, 2015 at 4:00 pm

    I tried it but as the instalation is abt to be complete it gives an error and says I should use “turn windows features on or off”ioff” in the control panel to install but I cant cnt downdownload the required files it keeps failing….plz help guys

    • Ian Matthews
      Ian Matthews July 28, 2015 at 7:40 pm

      I have not seen this fail but I would review the last two paragraphs in this post and confirm that you do NOT see any .NET updates/patches installed.

  9. levinho June 24, 2015 at 6:50 am

    I have tried every method but the same errors appear, where can i find the windows 8.1 pro installer in the C drive

    • Ian Matthews
      Ian Matthews July 28, 2015 at 7:42 pm

      I would review the last paragraphs in this post and ensure you do not have any .NET 3.5 patches installed. If that fails I would try the System File Checker (SFC /SCANNOW)

  10. Gustavo June 16, 2015 at 9:57 am

    Excellent !! It worked like a charm !! Thanks

  11. Hemant sutar May 12, 2015 at 10:00 pm

    thank you dear!

  12. Gary April 16, 2015 at 1:26 pm

    I have KB2966826 installed on my surface pro 3 right out of the box and Windows will not allow me to uninstall it. This is preventing me from installing .Net 3.5. The Microsoft knowledgebase is not very helpful and I need to get this resolved. Any ideas?

  13. Devon March 5, 2015 at 2:34 pm

    For all who are in a company environment that uses active directory policies and WSUS you must move your computer out of the OU its in , and place it in the computers Container. after doing so , go to cmd and type gpupdate /force and then reboot and then it will work GUARANTEED.

    • Ian Matthews
      Ian Matthews March 22, 2015 at 12:44 am

      I would not want to Guarantee that answer as there are several causes for this problem, but I hope your solution helps someone so we will post it 🙂 Thanks for your comments.

  14. Noop November 21, 2014 at 4:48 am

    Thank you my dear friend i spent 4 days bashing my head how to solve it and finaly you helped me!!!Keep up the good work and stay awesome! 😀

  15. Vortexo November 4, 2014 at 5:12 pm

    Thanks for the quick tip Ian. Hat off to you.

  16. Tim October 30, 2014 at 11:13 am

    This solution defies all logic but that’s MS for ya. Btw, it did solve my (very frustrating) problem, thanks!

  17. JT October 22, 2014 at 9:25 am

    THANK YOU!!!!!!!!!!!!!!!!!!!!!!

  18. Juan Vega October 21, 2014 at 9:57 pm

    I thank you very much worked to perfection

  19. theCoder13 October 21, 2014 at 2:13 pm

    I have Win 8.1 Pro. Update History shows KB2966828 install succeeded with the date, but in Uninstall an update it is not listed. Please help me to get this removed? I urgently need the .net 3.5

  20. balachandar.k October 17, 2014 at 9:40 pm

    thanks you boss

  21. Shashank October 15, 2014 at 12:17 am

    Thanks for your post, it really helped me to install .net 3.5 on server 2012.

  22. yul October 11, 2014 at 6:12 am

    I have win8. there is no KB2966826, KB2966828 and KB2966827 on the list. help please. 🙁

    • Ian Matthews
      Ian Matthews October 15, 2014 at 5:13 pm

      Perhaps your machine has a different issue. Have you tried running the system file checker? Start a CMD prompt as an Administrator and type SFC /SCANNOW . After it is done, reboot and try the .Net install again.

      I hope this helps.

  23. Che October 9, 2014 at 3:30 pm

    I can’t thank you enough. Bought a software and could not install cos of this error. CMD prompt code was a quick fix. Thanks

  24. Ben October 9, 2014 at 12:06 pm

    Thanks so much!
    For me uninstalling KB2966828 did the trick.

  25. Wes October 9, 2014 at 9:45 am

    Thank You, worked for me!

  26. Ahmad Alkhateb October 8, 2014 at 8:07 am

    This video works with me 2 100%

  27. Vins1970 October 8, 2014 at 4:48 am

    Could you help me? I can not uninstall KB2966826. In the control panel, when I select KB2966826, disappears the uninstall button. If I try to uninstall KB2966826 from the command prompt as an administrator, the system responds by saying that the security updates can not be uninstalled.

    • Ian Matthews
      Ian Matthews October 15, 2014 at 5:16 pm

      I have not seen that problem. If it was a recent install, you could try rolling your machine back to an earlier RESTORE POINT. Please let us know how it goes.

  28. RobZ October 8, 2014 at 3:22 am

    Brilliant – 1 Niggle
    Uninstalled Update (in my case 2966828),
    Rebooted and retried DISM cmd

    Failed with exactly same error message !!!

    then re-tried to install through the Control Panel and it WORKED!

  29. jha October 7, 2014 at 2:45 pm

    Thank you!

  30. Sharon October 7, 2014 at 10:51 am

    A million thank yous! This article worked for me.

  31. bahman October 3, 2014 at 10:11 pm

    for me, uninstalling KB2966827 did the trick

  32. Paulo Geneses September 29, 2014 at 9:18 am

    Worked for me too!
    Thanks, very much!

  33. Adriano September 29, 2014 at 7:43 am

    Thanks, solved my problem.

  34. Andrey September 29, 2014 at 1:22 am

    Excellent! It works for me!
    Thank you very much!

  35. SimonP September 28, 2014 at 8:36 pm

    Nice one.
    Thanks. Worked a treat.

  36. jmrula September 22, 2014 at 11:13 am

    This solved a problem I’ve been having for a while and have never found a fix for! Thanks so much!!

  37. beguiles September 18, 2014 at 8:40 am

    Hell Yeah! That worked for me. Thanks dude!!!

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