You can use Windows Disk Management to set your system drive letters.
DRIVE 1: C and D
DRIVE 2: E and F
CD/DVD 1: DRIVE R
CD/DVD 2: DRIVE S
MEDIA READER: DRIVES W, X, Y and Z
Whatever I plug in after that usually gets DRIVE G:
This has worked well for me since WIN2K....now WIN 7.
VAPCMD
I have a desktop with several drives: Hard drives C and D; CD/DVD drives E and F; a Yedata memory-card reader/floppy-drive combo (mem card section virtually useless because it won't read bigger than a 4 GB card); 4-slot external mem card reader on USB; NASbox drives P and Q. Problem: When I turn on a 1 TB external drive for backup, that I/Omega drive "steals" drive P, leaving that network drive inaccessible until I disconnect that USB drive and reboot. I have a "blank" in the drive list; drive I: was once the I/Omega drive; now, Drive I: is not found in the drive string.
I thought that I could have drives A: through Z: if I wanted to do that. So why are the drive letter assignments somewhat unstable? What is causing this apparent limit of nothing above Drive Q:? I have it figured that I should have probably nine more letters available. And, most importantly, what must I do to solve the "stolen drive letter" problem? Is there any way to "lock" in the drive letter assignments? I do not post often, but I have been reading posts; and I think I came to the rigt place for help on this one.

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