USB mass storage device not getting drive letter

[ykhan]

I got an external USB hard disk enclosure. It works fine on my laptop,
it gets detected, drivers get loaded, and everything shows up fine in
Device Manager, and a drive letter is assigned to it. When I put the
same device onto my desktop, almost everything happens the same,
except it doesn't get a drive letter assigned to it. I don't see it in
Disk Manager.

All computers are running XP SP2. I've tried it in a second desktop PC
with XP SP2 as well, and exact same thing happens -- no drive letter,
no recognition from Disk Manager, but Device Manager sees it fine
doesn't find any problems with it.

Yousuf Khan

 

[none]

Do you already have a drive Z:?

Can you set a drive letter from Device Manager, under properties?

 

[YKhan]

Do you already have a drive Z:?

Can you set a drive letter from Device Manager, under properties?

No, as I said, it doesn't show up as a disk under Disk Manager, but it
does show up as a device under Device Manager.

Yousuf Khan

 

[Alan Walpool]

Try using diskpart from the commandline to assign a drive. Hope this
works it has worked for me when I needed to make a drive showup. Could
be something else.

Later,

Alan

ykhan> I got an external USB hard disk enclosure. It works fine on my
ykhan> laptop, it gets detected, drivers get loaded, and everything
ykhan> shows up fine in Device Manager, and a drive letter is
ykhan> assigned to it. When I put the same device onto my desktop,
ykhan> almost everything happens the same, except it doesn't get a
ykhan> drive letter assigned to it. I don't see it in Disk Manager.

ykhan> All computers are running XP SP2. I've tried it in a second
ykhan> desktop PC with XP SP2 as well, and exact same thing happens
ykhan> -- no drive letter, no recognition from Disk Manager, but
ykhan> Device Manager sees it fine doesn't find any problems with it.

ykhan> Yousuf Khan

 

[Yousuf Khan]

Try using diskpart from the commandline to assign a drive. Hope this
works it has worked for me when I needed to make a drive showup. Could
be something else.

Didn't work.

I heard somewhere that the USB mass storage driver doesn't seem to work
in a system with more than one hard drive (which is the case for all of
my desktops)?

Yousuf Khan

 

[Guest]

Sorry Alan,
Can you please give me a step-by-step on that, as I am having the same
problem - device is installed and shows as working properly in Device
Manager, but does not show as a removable disk drive in the "My Computer"
window.

Thanks,
Nicole

 

[George Macdonald]

I got an external USB hard disk enclosure. It works fine on my laptop,
it gets detected, drivers get loaded, and everything shows up fine in
Device Manager, and a drive letter is assigned to it. When I put the
same device onto my desktop, almost everything happens the same,
except it doesn't get a drive letter assigned to it. I don't see it in
Disk Manager.

All computers are running XP SP2. I've tried it in a second desktop PC
with XP SP2 as well, and exact same thing happens -- no drive letter,
no recognition from Disk Manager, but Device Manager sees it fine
doesn't find any problems with it.

Do you have partitions and/or network drives on your desktop? I've had
trouble with "collisions" between drive letters and I'm still not sure of
the rules - sometimes it seems that a drive letter "sticks" with removable
drives across systems. In Device Manager for the drive, from the Volumes
Tab click on Populate and see what drive letters it wants to use and a
possible collision, then go to Disk Management and fiddle with the drive
letters.

 

[Guest]

Okay - I have sorted it out! The PC had assigned the same drive letter to
the USB drive as to a network drive. I went into Disk Management, (through
Control Panel, Administrative Tools, Computer Management) and re-assigned a
different (unused) drive letter to the USB drive - problem solved!

Thanks for the other posts, which helped me look in the right direction!

Nicole

 

[GSV Three Minds in a Can]

Bitstring <[email protected]>, from the

Do you have partitions and/or network drives on your desktop? I've had
trouble with "collisions" between drive letters and I'm still not sure of
the rules - sometimes it seems that a drive letter "sticks" with removable
drives across systems. In Device Manager for the drive, from the Volumes
Tab click on Populate and see what drive letters it wants to use and a
possible collision, then go to Disk Management and fiddle with the drive
letters.

They shouldn't stick across systems, but they will definitely stick
across time - i.e. if a WinXP system has ever seen a formatted drive it
will have the (last) drive letter stored in the registry, which can
cause all sorts of confusion later. Usually it seems to work out OK, but
sometimes ..

 

[Robert Myers]

No, as I said, it doesn't show up as a disk under Disk Manager, but it
does show up as a device under Device Manager.

How do the device driver details compare on the two machines?

RM

 

[Yousuf Khan]

How do the device driver details compare on the two machines?

They're almost identical, except for the no drive letter thingy.
Actually I don't have access to that machine where it's working right
now, that's in Montreal. I use (or was planning to use) this USB hard
disk to transfer files back and forth between my two setups in Ottawa
and Montreal (whereas previously I used to bring the whole laptop with
me when coming back to Ottawa).

Yousuf Khan

 

[daytripper]

Didn't work.

I heard somewhere that the USB mass storage driver doesn't seem to work
in a system with more than one hard drive (which is the case for all of
my desktops)?

Yousuf Khan

I have 6 sca drives across two hbas, four optical drives, and 3 emulated CDs,
a SM/CF combo usb mass storage device plus a "thumb drive", all running under
XP Pro. No issues.

I think you're still missing a driver. Maybe the chipset drivers didn't
install correctly?

/daytripper

 

[Bob Niland]

Do you already have a drive Z:?

Does XP support environment variable LASTDRIVE ?
If so, is there any chance it's set to something
other than Z ?

My guess is that this isn't a productive line of
inquiry, as my various Win2K docs are entirely
silent on the topic, so chances are it's not an
XP feature.

 

[Leo]

My USB drive works fine on a system with two other hard drives.

Get TweakUI and be sure to set last drive to Z.

--

LEO

The supply of government exceeds the demand.

 

[Yousuf Khan]

Does XP support environment variable LASTDRIVE ?
If so, is there any chance it's set to something
other than Z ?

No, I haven't seen the lastdrive used since the DOS days, and even then
in the last days of DOS, they were already defaulting to Lastdrive of Z.
I have plenty of drive letters available, just none of them are used
by this drive.

Yousuf Khan

 

[Scott Alfter]

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Didn't work.

I heard somewhere that the USB mass storage driver doesn't seem to work
in a system with more than one hard drive (which is the case for all of
my desktops)?

With three hard drives installed in my home desktop, it'd be a bummer if my
USB hard drive didn't also work with it.

I'm assuming that the drive is already partitioned and formatted. When you
plug it into your desktop and bring up the Disk Management plugin, is it not
showing up at all? The drive and its partitions should show up there,
whether one or more drive letters are allocated to the drive or not. I've
had parts of flash-card readers not get drive letters when they're plugged
in because they were already taken by network shares or other drives; going
into Disk Management and reassigning drive letters has always cleared up the
problem for me.

_/_
/ v \ Scott Alfter (remove the obvious to send mail)
(IIGS( http://alfter.us/ Top-posting!
\_^_/ rm -rf /bin/laden >What's the most annoying thing on Usenet?

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iwQJfGLzdvmFX0ZM0jKQu5c=
=TmWr
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[Franc Zabkar]

I got an external USB hard disk enclosure. It works fine on my laptop,
it gets detected, drivers get loaded, and everything shows up fine in
Device Manager, and a drive letter is assigned to it. When I put the
same device onto my desktop, almost everything happens the same,
except it doesn't get a drive letter assigned to it. I don't see it in
Disk Manager.

Is a USB pen/thumb/flash drive assigned a drive letter?


- Franc Zabkar

 

[cquirke (MVP Windows shell/user)]

Bob Niland wrote:

No, I haven't seen the lastdrive used since the DOS days

One of the things that can hide a drive letter in XP, is a network
share with the same drive letter. This applies both to USB sticks and
to hard drive volumes.

Suspect this if Drive Manager shows the device (drive, volume) but you
don't see it in Windows Explorer. Use Drive Manager to set a
different drive letter so that it escapes the shadow of the LAN share.

---------------- ----- ---- --- -- - - - -

Cats have 9 lives, which makes them
ideal for experimentation!

 

[George Macdonald]

Bitstring <[email protected]>, from the


They shouldn't stick across systems, but they will definitely stick
across time - i.e. if a WinXP system has ever seen a formatted drive it
will have the (last) drive letter stored in the registry, which can
cause all sorts of confusion later. Usually it seems to work out OK, but
sometimes ..

In a perfect world, GUIDs (Globally Unique IDs) *really* are unique.
I've seen some oddball behavior which I cannot explain.

 

[YKhan]

Suspect this if Drive Manager shows the device (drive, volume) but you
don't see it in Windows Explorer. Use Drive Manager to set a
different drive letter so that it escapes the shadow of the LAN

share.

No, "Drive" Manager (actually is "Disk" Manager, but I know what you
meant) is not showing it at all as a volume. If it showed up in Disk
Manager, I would've known what to do with it then.

Strangely enough, now this drive is not showing up on its original home
either, where it was working previously. I'm going to have see what
else is going on here, maybe something got shaken loose while I was
transporting it?

Yousuf Khan