Updating to Vista SP1 (KB936330) and get error 800F0900?

I have Vista Ultimate 32 bit and tried to update to SP1 both manually and through Windows Update. I got the error message when using Windows Update. I've also tried to rename the edb.chk and had no luck with any. Any suggestions?

The problem seems to have resulted from corruption of mmcico.dll which I
understand is a multimedia file. Through several attempts I was unable
to resolve the corruption.

The end resolution was to perform an in place upgrade installation of
Vista.

Basically, insert install disk and pick upgrade from the install
options. After a couple of hours I had a functional Vista machine again,
which I walked through all the updates, including SP1.