This copy of Windows is not genuine
I read somewhere that I could use the same MSDNAA key for two installations, but maybe that was false. The other possible issue may be that I recently shuffled partitions around on my hard drive using GParted, leading to Windows being unable to boot and the use of recovery tools to correct filesystem errors, edit the boot manager, repair the MBR, among other things. My Windows 7 partition survived this, as I can boot into it and all my data is there, but maybe "something happened".
It doesn't ask me to call Microsoft, or to reactivate it, or to download some tool to validate it, or to do anything else, for that matter. I'm not sure how I'm supposed to convince it that it is, in fact, a genuine copy of Windows.
I also have a MSDNAA key for Windows 7 32-bit, and I read somewhere that I can use it for a Windows 7 64-bit installation. Is this true, and do you think doing this would fix my problem? (However, I don't know how to enter a new key.)