Windows 2003 standard will not upgrade to enterprise

[Guest steve@mcmillaninc.com]

I have a windows 2003 standard server service pack2 that I would like to

upgrade to enterprise. We do have MS Virtual Server 2005r2 running on it.

 

When I try to run the upgrade to Enterprise, I receive an error message that

"Setup cannot continue because the version of Windows on your computer is

newer than the version on the CD."

 

Any ideas? Thoughts?

 

Thanks in advance!

Steve