Actually Pegasus' reply is mostly true but not all applications installable
on XP can be installed on 2003 Server. It also depends if the developer done
an OS check in his/her code, which I always do when coding applications for
minimum requirements
Example: Windows Live would say something like cannot run on this platform.
I have a 2003 R2 domain controller at home running my network & are other
things cannot be installed on there & others are made for server OS' instead
like WSUS (which can be spoofed onto XP).
Also things like XP SP3 won't install on 2003, yet XP SP2 64 bit is written
for both XP & 2003
Some printers will install on XP but not 2003 R2 even using the XP drivers.
So, it depends on the software
