Long story short, I have several HDD and one SSD. The SSD was my boot "C" drive and single win 7 OS. The SSD failed so I installed Win 7 on one of the back-up HDD. The install made that drive "C". I replaced the SSD and installed WIn 7 as a second OS on the SSD and it became drive "B". I can boot to either OS install on start-up but regardless of which install I boot with, drive "C" becomes the active system drive, even though the desktops are different (as they shoujld be for the two OS installs). SO, even if I boot from the SSD "B" drive, in windows disk manamgent it indicates that "C" is the "system" and "active" drive while it will indicate that "B" is the "boot" drive.
I want to format drive C so I can change its drive letter and reinstall Win 7 as a single OS to the SSD and make it drive "C", but windows will not let me change drive letters or format the current HDD labeled as "C" - obviously because it considers it the active sytem drive even when I've booted from the "B" SSD.