Getting Windows IE to prompt for the XAMP plugin install

I'll start with the obvious I *hate* IE. That said, I've been working with the RHEV3 Beta, and love having an alternative to VMWare.

I have gotten the Admin portal to work once by flailing with IE/trusted sites/XAMP permissions for hours, but frankly don't know what twist got it to prompt for the XAMP install.

Since then, I've tried on 4 different machines to get the install to work with no luck - various combinations of XP/WIN7 with IE7/8/9.

Per documentation I'm setting the RHEVM server site as trusted, enabling XAMP download & installs - obviously I'm missing something, and I hope someone here knows the trick.

TAT