Target Designer: Error-Index specified does not reference an exist

[Guest]

I'm using XPe SP1 (live; not evaluation) with a fair number of QFEs
installed. Until recently, I've been able to build images that work.

Then, for reasons unknown to me, TD no longer will complete a build. The
only change to my PC (aside from possible changes by Windows Update) was
installation of Nero 7.

A previously buildable SLX file now yields an error that says:

An internal error occured while building the run time image. code=0x800a004c
Description=Index specific does not reference an existing item in the collection.

The error occurs occurs in the same place every time:

"Building Enhanced Write Filter - Hotfix Q823025 [Version 2.0.1901.2, R1902]

The dependency check reveals no errors/warnings.

Prior to the "internal error" occurring, there are hundreds of file not
found error messages.

I checked some of the "file not found" errors and the files appear in the
repository.

Clues would be appreciated. I'm not looking forward to having to (yet again)
re-install all of this stuff.

Thanks.