Thanks for your post...
Actually, it is every installer that I've built since upgrading to AdminStudio 3.5. This includes Adobe Acrobat 5, Adobe Photoshop 7, JMP 5 from SAS, MATLAB R13 from MathWorks, Mathematica 4.2 from Wolfram Research. All of these installers were actually built on Windows 2000 so I'm a little befuddled as to why that is the one OS that they don't work on. If we restart two times in a row with the Last Known Good Configuration option, it does eventually let you log in and the machine works fine, albeit a little slow for the first time. Every time after this, the machines work fine. As I stated before, XP, 98, ME are all OK running these installers.
Thanks for any additional information.