Drive letters keep getting reassigned

L

Lorne

I run software from attached USB drives and from virtual disks so it is
essential that the drive letters do not change but about once a week they
all get reassigned without me doing anything.

What in XP can do this behind my back? I think the first occasion it
happened was after I had to boot in safe mode to troubleshoot a problem but
since then it has happened 3 more times.

In case it makes any difference the correct drive assignmenets that I want
to keep are:

A: Floppy
B: RAM disk
C & D: hard disks
E: vacant waiting for USB disk to be attached
F & G: DVD drives
W, X, Y & Z: virtual DVD drives

When the reassiggnment takes place the DVD drives become E & F and the
virtual drives become G-J so USB drives use H.

I know how to reset them but I want to stop it happening in the first place.
 
S

Shenan Stanley

Lorne said:
I run software from attached USB drives and from virtual disks so
it is essential that the drive letters do not change but about once
a week they all get reassigned without me doing anything.

What in XP can do this behind my back? I think the first occasion
it happened was after I had to boot in safe mode to troubleshoot a
problem but since then it has happened 3 more times.

In case it makes any difference the correct drive assignmenets that
I want to keep are:

A: Floppy
B: RAM disk
C & D: hard disks
E: vacant waiting for USB disk to be attached
F & G: DVD drives
W, X, Y & Z: virtual DVD drives

When the reassiggnment takes place the DVD drives become E & F and
the virtual drives become G-J so USB drives use H.

I know how to reset them but I want to stop it happening in the
first place.

http://www.uwe-sieber.de/usbdlm_e.html
 
L

Lorne

Shenan Stanley said:

It looks like that software will allow me to reserve drive E for USB devices
but it does not address the key issue of why the drives get reassigned in
the first place, nor does it appear to be able to force the virtual drives
to use W thru Z. There should be no need to run separate software because
Windows is supposed to remember which drives are used by which pieces of
hardware through the registry key:

HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices

but my problem is that something is changing these keys.
 
P

philo

Lorne said:
I run software from attached USB drives and from virtual disks so it is
essential that the drive letters do not change but about once a week they
all get reassigned without me doing anything.

What in XP can do this behind my back? I think the first occasion it
happened was after I had to boot in safe mode to troubleshoot a problem but
since then it has happened 3 more times.

In case it makes any difference the correct drive assignmenets that I want
to keep are:

A: Floppy
B: RAM disk
C & D: hard disks
E: vacant waiting for USB disk to be attached
F & G: DVD drives
W, X, Y & Z: virtual DVD drives

When the reassiggnment takes place the DVD drives become E & F and the
virtual drives become G-J so USB drives use H.

I know how to reset them but I want to stop it happening in the first place.


You need to use the same USB port each time ....for your external drive.
 
L

Leonard Grey

Windows XP automatically assigns the next available drive letter when a
new device is added. That's just how it works. Don't forget, when
Windows XP was being designed, way back in 2001, nobody was using USB
devices the way we do now. So the thing to do is just shrug and use
Uwe's software.

Another workaround, if you don't require a separate drive letter, is to
mount USB drives as NTFS mount points. That gives your drive(s) a fixed
path.
 
L

Lorne

philo said:
You need to use the same USB port each time ....for your external drive.

But that is not the issue. XP is supposed to remember which drives were
last used via the registry entries at
HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices but these entries are being changed
by something.

If a DVD drive gets moved from drive F to drive E I can never load the USB
in drive E, nor can I use any software in the DVD drive that requires the
DVD to be drive F.
 
L

Lorne

Leonard Grey said:
Windows XP automatically assigns the next available drive letter when a
new device is added. That's just how it works. Don't forget, when Windows
XP was being designed, way back in 2001, nobody was using USB devices the
way we do now. So the thing to do is just shrug and use Uwe's software.

But the software does not solve my virtual DVD problem. I have software
running from virtual DVD drives that require the drive letters of those
drives to stay constant (else I have to reinstall).

Something is editing the registry entries at
HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices and those entries are what XP uses
to remember the last drive used for each connected device.
 
L

Leonard Grey

You can argue with your fellow users or you can use the workarounds and
get on with it.
 
B

Bill in Co.

Lorne said:
But that is not the issue. XP is supposed to remember which drives were
last used via the registry entries at
HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices but these entries are being
changed
by something.

If a DVD drive gets moved from drive F to drive E I can never load the USB
in drive E, nor can I use any software in the DVD drive that requires the
DVD to be drive F.

Why can't you permanently assign the DVD drive to a higher letter in Windows
Explorer? That's what I did, to avoid this problem.
 
L

Lorne

Leonard Grey said:
You can argue with your fellow users or you can use the workarounds and
get on with it.

Nobody has suggested a workaround for the virtual DVD drives which are also
being changed. The setup I have has worked for 4 or 5 years and suddenly
failed so it is not unreasonable to try and find out why.
 
B

Bill in Co.

Lorne said:
Nobody has suggested a workaround for the virtual DVD drives which are
also
being changed. The setup I have has worked for 4 or 5 years and suddenly
failed so it is not unreasonable to try and find out why.

I think I gave you one way (of assigning a permanent, higher letter, drive
letter to a DVD drive, but not a "virtual" DVD drive, whatever that is.)
 
L

Lorne

Bill in Co. said:
I think I gave you one way (of assigning a permanent, higher letter, drive
letter to a DVD drive, but not a "virtual" DVD drive, whatever that is.)

That is how it is set up. The real DVD drives are permanently set to F & G
drives, the virtual ones to W, X, Y, Z. These settings are stored in the
registry but my problem is that something is changing the registry and every
week or so they get reassigned to E thru J and it is the reassignment that I
am trying to stop.
 
B

Bill in Co.

Lorne said:
That is how it is set up. The real DVD drives are permanently set to F &
G
drives, the virtual ones to W, X, Y, Z. These settings are stored in the
registry but my problem is that something is changing the registry and
every
week or so they get reassigned to E thru J and it is the reassignment that
I
am trying to stop.

OK, I don't know anything about virtual DVD drives, but noting the drive
letters being used above, could it possibly avoid the problem if you simply
reassigned the real DVD drives to some higher letters (like J and K), so
that presumably there wouldn't be any potential conflicts?

Or perhaps simpler yet, why not simply use System Restore to go back to the
restore point that predated this weird behavior (since you implied it just
happened)?
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Top