I have a PC with Windows XP Home SP3 OS currently installed. I now have a need to get this pc onto a Windows 2k8 R2 Domain. I dont want to upgrade to Windows 7 because of having to reformat as part of process. So my question is whether I will be able to upgrade/downgrade the pc w/XP Home SP3 to Windows XP Pro SP2? I have an unused XP Pro SP2 license but worry that the OS will see the upgrade as SP2 and therefore not install. If this is the case, Does anyone have suggestions to get around this? Uninstall SP3 on XP Home PC?