Windows 7: Excel 2010 Configuration Starts Every Launch (on VM's)

I am running a Windows 2008 SP2 server with three virtual machines, each running Windows 7 Professional 64 bit SP1. Each virtual machine is running a separate licensed copy of Excel 2010 (not Office). No previous versions of any Office product have ever been installed.

Every time any user starts Excel on any virtual machine, the splash screen comes up and then "Please wait while Setup prepares the necessary files" and it goes through a lengthy configuration process. After that, Excel runs fine. Until it's closed.

I've researched this for three months now, and none of the "fixes" I've found apply to my situation or worked when I did try them. Some of the more complex "edit your registry" fixes frankly scare me when I have remote users all over the country depending on the VM's being up and running.



Most of the Microsoft answers in their knowledge base are a few years old.

Any guidance on even where to start looking? Seems like it should be a simple fix, but I sure can't find it!

Thanks for any ideas.