Yes, if you use either xpconvert or TweakNT or NTSwitch to change the platform ID of any VLK edition of Windows XP or 2k3, it will cause a problem. It's easily circumvented, but like TweakNT, discussion of the method and any tools required is frowned upon. It can be done, but honestly, you will still run into a few apps that will give you grief as your OS is still server 2003. At least with xpconvert, it leaves it so the OS is still detected as server. Most of the apps I've had trouble with will either install in compatibility mode or in the case of msi installers, a droped row in the launch conditions using orca or qwerty.msi will get around it. I'm not sure about TweakNT as it's been many years since I've messed around with it.