Can I use the B: drive on my PC?

September 29, 2008 6:32 PM

Can I use B: as a drive letter, on a modern windows PC, without messing things up?

Doing some reading, I have learned that there's no B: drive on most PCs because B: used to be the letter for the 2nd floppy disk; most don't have it anymore, so the B: has become archaic.

But I don't see any reason not to use a perfectly good letter.

Is there any reason that I can't assign an external drive to B: (for Backups, duh)?

Would it cause some kind of system irregularity?

How about a networked share? If I've networked all the computers in the house/office/domain, and can I map their backups to B: without causing any wonkiness?

Does this differ from XP to Vista?

B: might actually be special to the system in some way that would make it incompatible, and if so, Fine, I'll leave it alone.

But if it's not any different than F: or Q:, then I'd like to know I'm free to use it without any extra worries.

posted by penciltopper to computers & internet (11 answers total)

Absolutely no problems with this at all.

XP and Vista both allow you to make a drive B:. (Start --> Control Panel --> Administrative Tools --> Computer Management --> Storage --> Disk Management --> Right click on a share --> Change drive letters & paths)

They wouldn't let you do this if it would royally screw something up. It's just archaic like you described; C: became the de facto boot drive, so MS figured that STARTING the next physical or logical partition at B: would be RIDICULOUSLY confusing to typical users. And they're totally right.

But it's completely free game. Go forth and B:!
posted by disillusioned at 6:44 PM on September 29, 2008 [1 favorite]

It's possible that some idiot app programmer checks to see if something's on B and then assumes it's a floppy drive. But this would have to be a pretty old app, and I don't know why they'd do this in the first place.
posted by aubilenon at 7:08 PM on September 29, 2008

I wouldn't do it.. for too many years, B == floppy. You've got 23 other letters to choose from, why take chances?
posted by Nelson at 7:38 PM on September 29, 2008

I use it for network drive letters all the time. It's because the networks I walk into often have the same shared folder as different drive letters on different computers (neither I nor anyone that works for my company set it that way), so B is always unused, and since I need the same drive letter all across the network, it gets used.
posted by deezil at 8:19 PM on September 29, 2008

The B: drive, for people who didn't have two physical floppy drives, acted as a logical floppy drive. You could do something like COPY A:FILE.TXT B: and DOS would read the file into RAM and then ask you to change the disk. (Actually, since the built-in COPY command sucked so much, it would read part of the file into RAM and make you switch disks five gazillion times. But I digress.)

You probably won't run into any trouble. But you're more likely to run into trouble than if you used D-Z. There are so, so many applications out there that make stupid assumptions that work 99.999% of the time. Why bother violating that?
posted by grouse at 8:33 PM on September 29, 2008

It's also possible to make a recursive subdirectory in the same Disk Management snap-in, which will royally screw up many programs, so I wouldn't go so far as to say that it's not possible to royally screw things up in that particular control panel.
posted by zixyer at 1:54 AM on September 30, 2008

Another royal screwup you can perform with Disk Management is assigning an external USB drive the same drive letter as a mapped network drive. Whenever you put such a USB drive in your computer, you get the Connected ding, but nothing shows up under My Computer. It's most annoying.

In fact, Windows will do this very thing all by itself when it assigns a default drive letter to a new USB device, which is even more annoying.

And that is why I start my network drive mappings no lower than N: instead of the far more common H:. If your org is set up with home folders mapped to H: and you get a new batch of PCs with an inbuilt multi-format card reader, you're pretty much hosed even before people start plugging in their USB sticks.

Drive letters suck.
posted by flabdablet at 2:42 AM on September 30, 2008

If you don't want to worry about drive conflicts, use NET USE * \\share, Windows will automatically assign an unused drive letter.

Depending on a single letter to be always available and assuming its mapped to your share/drive is pretty bad idea.
posted by wongcorgi at 12:59 PM on September 30, 2008 [1 favorite]

You can also use the subst command to get your drive to act like B: without actually being b: (works on folders).
posted by Four Flavors at 4:02 PM on September 30, 2008

opinions seem divided. sigh.

@wongcorgi: "Depending on a single letter to be always available and assuming it's mapped to your share/drive is pretty bad idea." -- Unless it's the B: letter, which would never be otherwise used or unavailable (as opposed to anything after C:) and that \\whatever\share is set to re-map as B: on startup when connected....
That was the idea anyway.

Perhaps I'll knock wood, cross my fingers, turn three times and spit, then try it on my own PC for a while, before messing with grandma's computer. Thanks to all.
posted by penciltopper at 4:26 PM on September 30, 2008

NET USE * \\server\share will start assigning drive letters from Z: downwards, which does minimize the chances of drive letter conflict with USB devices, whose letters are assigned from A: upward. Trouble with that is that some apps expect Z: to be available as a "scratch" drive letter for use with SUBST, and will fail if they can't have the use of it.

Sysadmins working in an environment where drive letters are the expected way to do things really would be well advised to stick to manual mappings between N: and T: as much as possible.
posted by flabdablet at 4:42 PM on September 30, 2008