VS2005 SP1 for Vista Not Installing

Giganews Newsgroups
Subject: VS2005 SP1 for Vista Not Installing
Posted by:  abakshi (abaks…@discussions.microsoft.com)
Date: Tue, 13 Mar 2007

I'm running Win Vista Ultimate x64 and installed VS2005, then ran MS Update,
which found a security patch for VS and installed it.  I then went and
downloaded SP1 for Vista, tried to installed it, and it gave this error (says
"Windows Installer" at top):

"The upgrade patch cannot be installed by the Windows Installer because the
program to be upgrade may be missing, or the upgrade patch may update a
different version of the program.  Verify that the program to be upgraded
exists on your computer and that you have the correct upgrade patch."

I tried restarting, to no effect.  Any ideas?