Windows Defender error: 0x8050800c

I am receiving the following error when Defender attempts to run a scan.

"Windows Defender encountered an error: 0x8050800c. An unexpected problem
occurred. Install any available updates, and then try to start the program
again. For information on installing updates, see Help and Support."

Current Info:
Windows Defender Version: 1.1.1505.0
Engine Version: 1.1.2704.0
Definition Version: 1.20.2743.1

This is a legit, activated, Vista Ultimate, system is a DELL GX620, running
Office 2007 and the latest VMWare Workstation. No other software installed.

I called MS support and went round and round for many hours over several
days trying to fix this issue. Some of the things that we tried were:

Running chkdsk /f /r, did not fix.

Running a system restore to a previous date, back to definition version:
1.19.2728.3 from 6/27/2007. Fixes the issue until the pattern gets updated.
Then I get the same error message.

I had also tried the suggestion for error 0x80240029, KB934562, which was
the rename the SoftwareDistribution folder to .old fix. This did not work
either.

One of the MS support technicians recommended a re-install/upgrade over the
top of my otherwise working system. I just felt this was such an extreme step
to take, but after doing a full image backup I figured I'd give it a shot as
I'm out of options at this point. It did not fix the problem even after I
installed all the Microsoft Updates after the "Upgrade" re-install over my
working system.

Before getting the above error, no other software had been installed for
several weeks except Microsoft Updates.

So I figured I would try my luck here with the community to see if anyone
has any other suggestions before I back-up all my data an re-install fresh
because ONE application is broken. (Lame)