Generally, the computer is pretty good
at keeping track of conventional storage
devices.
Where it screws up, is if you have a mapped
network drive - in that case, a defunct letter
might throw up that error, because the mapped
drive is no longer present.
Think carefully about what you did with your
Windows File Shares, and whether you ever
ticked a box that said to "connect it every
time I boot the computer". It would be
the attempts to make permanent network
mounts, that could throw up the error.
Another place of contention in the file system,
is the assignment of mapped network drives, and the
usage of USB sticks. They can "overlap" on letters,
leading to surprises. That's not your current
problem. Uwe has USBDLM for such things (sorting
it out).
All my network mounts are temporary, so
I never see your error. I don't even know how
to make a mapped drive :-) But I did use a
SUBST once, to get around a path length problem.
That's as close to adventurous as I get.
http://www.vfrazee.com/ms-dos/6.22/help/subst.htm
Paul