Microsoft has not made any pretense that the boot, Windows, the OS drive letter can be changed during install.
So when we start over, we are pretty much forced to go back to C:
But wait, maybe our old friend SUBST can help. Remember I can't know all about how your PC came to be with a V drive but how about SUBST V: over to C:?
http://en.wikipedia.org/wiki/SUBST
SUBST has been around for decades so I'll stop here.
Bob

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