Question

I have an old Vista box sitting around, and I'm thinking of upgrading it to Windows 7 64-bit, as it has 4gb of RAM. Well, I know that there's an "in-place" upgrade from Vista, but does it work from 32-bit to 64-bit?

Answer 1

Nope

Windows 32bit to 64bit has never been supported.

If you are a fan and trust upgrading, you may want to take a look at "Windows Easy Transfer". This should allow you to move your accounts, documents, settings and a whole lot more to a temporary location whilst you can do a full install of the new Windows, then move all your stuff back.

From Microsoft

32-bit and 64-bit Windows: frequently asked questions

Can I upgrade from a 32-bit version of Windows to a 64-bit version of Windows?

No. If you are currently running a 32-bit version of Windows, you can only perform an upgrade to another 32-bit version of Windows. Similarly, if you are running a 64-bit version of Windows Vista, you can only perform an upgrade to another 64-bit version of Windows Vista.

(this is from their Vista page, I cannot find it for 7, however I am 99.9999% sure it is the same!

Answer 2

Check this answer from Microsoft:

Click Here