It is not clear to me if I can buy the 'Upgrade' version of Windows 7 Professional if the version I have is Windows XP Home or whether I can only buy the non-upgrade 'Full' version. Everywhere I read states that Windows XP owners are eligible for an upgrade price for Windows 7.
However, I cannot find any reference whether you are limited to upgrading to the same edition/version/type of the OS. For example, only Windows XP Home can upgrade to Windows 7 Home and only Windows XP Pro can upgrade to Windows 7 Pro. Is this the case?
Can I buy the upgrade version of Windows 7 Pro even though I have Windows XP Home?
(I also understand that regardless of what I eventually purchase, it would need a full install of Windows 7 and not an upgrade of the OS itself. My question is more about the upgrade licensing terms and the eligibility of purchase.)