KB911565 update will not install

I've tried to install this 17 times and no go: Security Update for Windows
Media Player 10 for Windows XP (KB911565) Please help.

See this MS article
You cannot install some updates or programs
http://support.microsoft.com/kb/822798/en-us

Need for you to dig into the log file and see what it contains for the last session.
Use Notepad or Wordpad and take a look at (usually C:\WINNT or \Windows )
%windir%\WindowsUpdate.log

Scan down to the bottom. Review contents. Copy and paste back in reply "significant portions" for last session.
Be sure to get all the lines that contain "Error".

--
Maurice N
MVP Windows - Shell / User
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jdgriff wrote:
> I've tried to install this 17 times and no go: Security Update for
> Windows Media Player 10 for Windows XP (KB911565) Please help.

Solution (at least for me)

1. Uninstall and re-install defender. I should revert to signature 1.0.0.0
2. Run Msiexec /x {A5CC2A09-E9D3-49EC-923D-03874BBD4C2C}, and then click OK.
3. This, I think, clears existing signatures.
4. Open Defender and find tab to right of questionmark
5 Click on it and find "update" and run it
6. Got the latest March updates OK