Subst and USB drives

G

Guest

Hi
I have a XP Pro SP2 machine with all patches on.
I use subst to map 3 drives to different paths (E:, N:, T:).
When I plug in a usb pen drive it is recognized, the drive installed, but no
letter is assigned, although I see the disk in disk manager.
If I remove the subst on drive E:, immediately the drive becomes visible.
Any ideas on the way to solve this?
Actually I remap the pen to another letter, so when I plug it it mantains my
assigned letter, but each new USB pen or external disk gets no drive letter.
Thanks
 
P

Pegasus \(MVP\)

Marcello Gorlani said:
Hi
I have a XP Pro SP2 machine with all patches on.
I use subst to map 3 drives to different paths (E:, N:, T:).
When I plug in a usb pen drive it is recognized, the drive installed, but no
letter is assigned, although I see the disk in disk manager.
If I remove the subst on drive E:, immediately the drive becomes visible.
Any ideas on the way to solve this?
Actually I remap the pen to another letter, so when I plug it it mantains my
assigned letter, but each new USB pen or external disk gets no drive letter.
Thanks

The USB drive takes the first available letter after the
physical drive letters. If that letter is taken by a network
drive or a substituted drive then the USB drive letter is
invisible. Move your substitute drive letter higher up, or
use diskmgmt.msc to assign a different drive letter to
your pen device.
 
G

Guest

The USB drive takes the first available letter after the
physical drive letters. If that letter is taken by a network
drive or a substituted drive then the USB drive letter is
invisible. Move your substitute drive letter higher up, or
use diskmgmt.msc to assign a different drive letter to
your pen device.

Ahemmm.... If I used that subst it is because I need THAT letter.
The workaround you wrote is the one I use (see my message).
If a letter is Substed or networked it is not THE FIRST AVAILABLE. I think
AVAILABLE=NOT USED.
I cannot find docs saying this is by design...
Thanks for the quick response
 
U

Uwe Sieber

Marcello said:
I use subst to map 3 drives to different paths (E:, N:, T:).
When I plug in a usb pen drive it is recognized, the drive installed, but no
letter is assigned, although I see the disk in disk manager.
If I remove the subst on drive E:, immediately the drive becomes visible.
Any ideas on the way to solve this?

To get rid of this 'first free letter assignment' I wrote
a small Win32 service. Using it you can define default
letters for USB drives.
http://www.uwe-sieber.de/usbdlm_e.html


Greetings from Germany

Uwe
 
U

Uwe Sieber

Marcello said:
Thanks for the tool but I still think this is a odd behaviour by XP, since
the first "free" letter is not free, it is in use bu Subst.

Yes it is odd. But it's by design that Subst and network drives
exist on user level only so they are neither accessible nor visible
to anything that works on system level.

If you configure some different letters in the USBDLM.INI
and a newly attached drive gets the first free letter (E
on you maschine) USBDLM it will immediately remount it to
the first free of the configured letters. I think that would
solve your problem.


Greetings from Germany

Uwe
 

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