How to fix error installing .NET Framework 1.1 SP1 on a computer that has MS05-004 installed

I recently encountered a .NET Framework setup problem that is not described in my previously published .NET Framework hotfix/service pack troubleshooting guide while doing some testing for the upcoming version of Windows Media Center.  I installed a computer with Windows XP Media Center Edition 2005, the .NET Framework 1.1 and .NET Framework hotfix 886904 (MS05-004).  Then I went to Windows Update and found that it detected that I needed to install the .NET Framework 1.1 SP1 and it classified this as a high-priority update.  When I tried to install it from Windows Update, it failed for me with a generic "installation failed" error message.

Of course, being the setup geek that I am, I wanted to figure out what was happening behind the scenes.  So I downloaded the setup package for the .NET Framework 1.1 SP1 from this location and ran it with full UI (instead of letting Windows Update run it for me in silent mode).  When I did this, I saw this error message:

.NET Framework 1.1 SP1 error dialog

This error message started me on the right track to find the solution to my problem.  I decided to check in Add or Remove Programs first to see if there were any hotfixes for .NET Framework 1.1 listed, and I found one named Microsoft .NET Framework 1.1 hotfix (KB886904).  Once I uninstalled that hotfix and rebooted, I was able to return to Windows Update and successfully install the .NET Framework 1.1 SP1.

Ordinarily, .NET Framework service packs have logic built into their setup packages to automatically uninstall hotfixes and then apply the SP.  That was not possible in this scenario because the fix for MS05-004 was not included in .NET Framework 1.1 SP1.  The underlying security vulnerability was found after .NET 1.1 SP1 was tested and signed off on within Microsoft but before it went live on Windows Update.  Since .NET 1.1 SP1 did not have this fix, it did not have knowledge of the hotfix package for MS05-004 and was not able to automatically remove it.  That is also why you see a new version of MS05-004 offered on Windows Update immediately after you install .NET Framework 1.1 SP1 (this time it is named KB886903 instead of KB886904).  Future service packs for the .NET Framework 1.1 will have the fix for this issue included, so you will not see this error message if, for example, you try to install the .NET Framework 1.1 SP2 on a computer with 1.1 and KB886904 installed in the future when 1.1 SP2 is available.

It is unfortunate that this type of setup scenario leads to a generic failure on Windows Update and does not help the average user find the solution to the problem.  I am not sure how many computers will have the exact combination of .NET 1.1 + MS05-004 installed before trying to install .NET 1.1 SP1, but hopefully if anyone does run into this they will be able to use the lesson I learned above to resolve the problem.


Comments (6)
  1. .net_hotfix_notfixed says:

    Hi I appreciate you taking the time to write this. i have a similar problem with the .net SP 1 failing install and im going to try your trick and se eif it works!!! i was wondering how you figured out which hotfix to uninstall since all mine are listed as generic Window sXP hotfix-KBxxxxxx in the add remove programs and there is 45 of them. did you look up each one and then have to correllate which were relate to .net …or did you just kow

    or is there somewhere else to look

  2. Hi .net_hotfix_notfixed – .NET Framework hotfixes are listed separately from Windows XP hotfixes, so you should be able to locate it by looking for hotfixes that begin with the name "Microsoft .NET Framework" Please contact me at if you have trouble getting this issue solved so that you can get the .NET Framework 1.1 SP1 to install successfully.

  3. Pat says:

    Follow these steps to figure out where the problem hotfix is…

    Here is how to tell which hot fix needs to be removed:

    Based upon the following two websites


    MCSE Tech site

    1) enable Windows Installer logging (see attached instructions below)

    Set (or add) these registry keys to enable Windows Installer (MSI) logging:


    String Value



    Set these registry keys to disable Windows Installer (MSI) logging:




    2) run setup to get the same error again

    3) use notepad to open the %temp%MSI*.LOG file

    4) search the log file for "FindQFEs" or just search for “Found blocking”

    You should see a line that says something like this:

    DDPatch: FindQFEs: Found blocking QFE at


    The problem patch is ‘U123456’

    5) use regedit and open HKEY_LOCAL_MACHINE and the rest of the path given in the log

    For example, open


    6) read the "Description" registry value. It will contain a string which

    looks something like:

    "Microsoft .NET Framework 1.1 Hotfix (KB884556)"

    7) open Add/Remove Programs from Control Panel. Uninstall this hotfix.

    Or just delete the entry for ‘U123456’ under


    Data from the log file created:

    DDPatch: FindQFEs: Found blocking QFE at SOFTWAREMicrosoftUpdates.NETFramework1.1M886904

    Info from the registry entry indicated above

    Description – Microsoft .NET Framework 1.1 Hotfix (KB886904)

    This fixed the problem:

    Deleted the registry key [HKEY_LOCAL_MACHINESOFTWAREMicrosoftUpdates.NETFramework1.1M886904]

    I was then able to deploy the .NET 1.1 SP1 update without problem.

    After this I deleted the registry keys created to log in install



  4. marios says:

    my only problem is that my antivirus finds a high risk potential threat with the related bulletin MS05-004, and that put me in thoughts. how can i remove it?

  5. Hi Marios – I’m not sure I understand your issue here. Do you have MS05-004 installed and your anti-virus software reports that this patch is a threat? Or is it saying that you have a threat and need to install MS05-004? Also, what anti-virus software are you using, and have you updated the software and signatures recently?

  6. Kelly says:

    I am trying to install windows vista service pack 1 and i keep getting a failed response with error 80070005. i looked at my update history and it just wont take. i notice that it installed the service pack 2. I am confused and have no clue what or how to get this installed. Why wouldn't it install the service pack 1 but installed service pack 2. please help me understand or what i can do to help fix this. thank you

Comments are closed.

Skip to main content