drive suddenly appears as two letters (USB)

Archived from groups: microsoft.public.windowsxp.hardware (More info?)

My external USB CD drive is normally assigned drive
letter I (established with Device Manager).

Now and then, Windows gets confused and stays that way
even when rebooted: this one drive appears twice, as
letters G and I, both in the "Devices with removable
storage" section of Explorer. Neither letter is fully
functional -- DirectCD Format sees only G but cannot
access it; Windows Explorer can eject only I, and cannot
open content on either letter.

Is this a known bug, or have others of you seen it?
What workaround or fix might exist? I've been able to get
back to a working state thus far, but have no confidence
this will continue to be the case.

Thus far, I've been able to restore normal function using
System Restore, but even that's become unreliable. (After
I recently turned off restoral for my secondary hard-disk
partitions, system restore to a working snapshot no
longer brings me back to the correct, single-CD-drive
state. But following this with a restore to the snapshot
just before I did the restore, oddly enough, does fix it.
For now.)

It's unclear what event (if any) causes this behavior to
surface. Sometimes, it's after I connect a second
external USB CD (which gets assigned G by default) -- but
the bug also appears when no changes have been made to
the set of drives.

OS: Windows XP SP1
drive: CD/DVD+RW, NEC ND-5100A, USB 2, in Dell MediaBase
other drives:
C/D/E/F are partitions on internal ATA hard drive
(Hitachi Travelstar DK23FB-40 40G)
H is FireWire CrossFire drive (XF160F)
J is USB 2.0 Maxtor drive (3000LE)
system: Dell Inspiron 300m (1.2G Pentium M, 384M)