KB969856 – Security update for Microsoft Virtual PC 2007 installs repeatedly

I had an issue with a Windows 2008 Server recently, where a security update for Microsoft Virtual PC 2007 would install successfully. However, after rebooting, Windows Update would request that I install it again. In the Windows Update history, it would show success, multiple times.

It turns out the problem was that I had Virtual PC 2007 AND Virtual PC 2007 SP1 installed side-by-side. I uninstalled my original Virtual PC 2007 (not SP1) and then applied the Windows Update and the problem was solved.

I’ve read of this same issue affecting Vista as well. Hope this helps anyone who encounters this problem.