Change system partition drive letter?

I did a clean install of Win7 to a partition from a running Vista system in another partition. The install assigned A: as the drive letter for the system disk. I built this installation up and it is my official installation. Things run fine but there is one confirmed application that thinks A: is a removable disk, there is Win7 help text that says A: and B: are reserved for removable disks, and the Windows Experience Index fails at the end of its calibration because it can't write a need file. I speculate that the WEI problem is related to the A: system partition but have no proof. I make this speculation because I had to do a recovery installation of Win7 to the same computer but a different partition on a different disk. I had to boot from the Win7 DVD to do this installation and it assigned the normal C: as the system drive. WEI completes fine when I boot this installation but I only needed this installation to get myself out of a hole I dug and fell into.

I can find no way to change A: to C: for my primary installation, not to mention that there are lots of registry entries referencing A:. I can change most of those with a global replace but parts of the registry of the running system are locked and can't be changed. Is there a reasonable way to switch A: to C:, short of reinstalling and rebuilding? Is it even worth the trouble?



New Member
I find it hard to believe that the installation assigned A by itself considering it's reserved for floppy etc. Either way it will just be a hell of a lot easier to just format the drive and reinstall, it's really not worth the hassle.

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