hey guys how can i fake XP sp1 over my win2003 sp1 install? i have that value in registry, it's "100" because i have sp1 but the program i want to install wants XP sp1 is there a solution to this?

any help would be appreciated. thanks.

To install an older version of Microsoft Windows over top of a newer version? NOT possible with Windows. With Windows, you can upgrade, but not downgrade.

The only other workaround would be IF the Windows 2003 Server Edition was an upgrade, that allowed a roll-back to the Windows version prior to the upgrade. And most likely, the Windows 2003 Server Edition is a full/clean install.

My best advice is to backup all your data from the machine running the 2003 Sever Edition, re-format the hardrive with NTFS, and install Windows XP.

By the way, what brand of computer/server is it?

Please post back with any progress or problems.