Continuing to be prompted by Microsoft Update after patch installation

Hi.

I was recently prompted by "Microsoft Update" about "Cumulative Security Update for Outlook Express 6 Service Pack 1 (KB837009)".  I installed the update (the dialog shows the download and the Microsoft "Installation Complete" Web page displays after the download/installation) but I am prompted daily by "Microsoft Update" to download and install the same update. I have downloaded/installed it several times but am prompted the next day to do it again.  It is as if a registry entry that needs to be present (to show that installation was done) isn't being made.

One suggestion was to delete the "C:\windows\system\catroot" folder.  I did this (after creating a backup of it) and that did not handle the situation.  I later restored the folder.

Does anyone know how I can handle this, without turning of the IE AutoUpdate feature?