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>In addition, what else does the "Windows Component Update" install ?
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The OS must be "up to date" - e.g. NT must be on SP6a, Win 2000 must be at least on SP1. (All the required update files are included on the CD.)

Additionally on my system (NT 4.0 SP6a), I had the following "required" updates:
Windows Installer 1.2
Setup Runtime files
IE 5.5 + Tools (You can start with IE 5.0x, but you can't finish with it <s>)
XML Parser v.3.0
MDAC 2.6+

Rick