ZDNet managed to get its hands on some, if not all, details regarding Windows 8 upgrade paths and although Windows XP, Vista and 7 will be getting it, there are quite a few restrictions.

According to the report, users upgrading from Windows 7 Starter, Home Basic and Home Premium will be able to upgrade to Windows 8 and even maintain their existing Windows settings, personal files and applications. Those that are looking to upgrade to Windows 8 Pro from Windows 7 Starter, Home Basic, Home Premium, Professional or Windows 7 Ultimate will also be able to keep their settings, personal files and applications. The same thing goes for those that are looking for an upgrade to Windows 8 Enterprise from Windows 7 Professional and Windows 7 Enterprise.

The Windows Vista (without SP1) and Windows XP SP3 users will be able to upgrade to Windows 8 but only personal files will be maintained while the rest of it will be gone. Those that run Vista SP1 will be able to upgrade and get their all personal data and system settings.

The restrictions include a cross-language installation and in that case you will only get your personal files while the rest of the settings, files and applications will be gone. There is no cross-architectuere installation as well, so if you are switching from 32-bit to 64-bit say goodbye to everything and do a clean install.

Earlier this month, Microsoft announced a Windows Upgrade Offer deal that gives you a chance to buy a copy of Windows 8 Pro fro US $14.99 in case you buy a Windows 7 PC between June 2nd, 2012 and January 31st, 2013.

Microsoft is expected to ship its new Windows 8 to manufacturers in July and it should hit retail/e-tail this fall.

You can check out more here.