Upgrading from 32- to 64bit Windows

It's not possible to upgrade a PC with a 32bit version of Windows to a 64bit Windows install, but you can perform a clean install of 64bit Windows 7. Here's how.

QUESTION: I have recently upgraded my PC from XP to Windows 7 Ultimate 32bit edition. I understand that the disc and activation code can be used again, so how can I activate the 64bit version using a 32bit-labeled disc?

ANSWER: There is no way to perform an upgrade from a 32- to a 64bit version of Windows; instead, you need to complete a clean installation of Windows 7 64bit. However, if your disc contains only the 32bit edition, you can't use it to install 64bit Windows. If your copy of Windows didn't come with two discs (one 32bit, the other 64bit), you may find your product key isn't valid for a 64bit installation. This will depend on the exact version of Windows 7 you purchased and whether it's an upgrade, OEM, or a full retail copy. Full retail copies should include a code for 64bit installations, but you'll still need the relevant disc – perhaps a friend has one you could borrow. If you haven't already checked, ensure your processor supports 64bit operation.