On one of my workstations, Windows 7 kept re-installing two updates, KB2468871 and KB2533523, even though the installations were successful each time.
KB2468871 is titled "Update for Microsoft .NET Framework 4.0 on Windows...". More details on this update can be found here.
KB2533523 has the same title, and more details on this update can also be found at Microsoft's website.
Some folks on the internet suggested downloading the update packages and installing them manually. So I did that. It did not help. Some suggested that the update should be done in safe mode. That did not work.
It turned out that for me, the cause of the problem was that I had a .NET 4 beta component installed, and I forgot to remove it. I saw it when I decided I was going to reinstall .NET 4. So I removed it. Now these updates are no longer trying to re-install themselves, finally.