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Windows 7 and Vista Activation FAQ: How do language, version, 64-bit or 32-bit, and source affect ability to install and transfer Windows licenses?
Recently my hard drive was corrupted on my laptop with 32-bit Windows 7 pre-installed. I heard you can re-register the serial keys to work with a new computer, erasing it on the older one, however I wish to upgrade to 64-bit Windows 7 in order to accommodate for more RAM expansions (aiming either for 8 GB or 16 GB). Is there any way I could do this without buying another OS?