Start Regedt32.exe (or Regedit.exe in Windows XP).Make a full system backup of the computer and system state.Note: In these steps, drive D refers to the (wrong) drive letter assigned to a volume, and drive C refers to the (new) drive letter you want to change to, or to assign to the volume. To change or swap drive letters on volumes that cannot otherwise be changed using the Disk Management snap-in, use the following steps:
This should be a rare occurrence and you should change the drive letters back to match the initial installation. This may happen when you break a mirror volume or there is a drive configuration change. The only time that you may want to do this is when the drive letters get changed without any user intervention. For the most part, this is not recommended, especially if the drive letter is the same as when Windows was installed.
