Something changed on your system. Only you can can possible know what that might have been. VC certainly didn't change itself. Windows may have updated itself, or you installed some new antivirus software, or changed your security or login credentials etc. There is not much point in us making wild guesses.
Sure, give it a shot. If it were me, I'd would want to know what had changed on my system, but if unzipping VC into a new folder works, then great.