Unkown Usb Device

[kfh]

Hi All,

I'm getting the above message when I plug in my pen drive. It did work on this partition and still does on my second partition, it also works on other machines. I've done all I can find on the net, including unistall of controllers in safe mode. Any ideas I may have missed something

Win Xp Pro SP2.

Thanks,

kfh.

[Paul Komski]

It did work on this partition and still does on my second partitionI don't follow. Which partitions are these?

[kfh]

Hi Paul,

I have two partitions on my machine, both Xp Pro SP2, my pen drive now only works on one of the partitions.

Thanks,

kfh.

[Paul Komski]

For partitions I guess we can read installations; two installations of WinXP both of which are on different partitions. If so I would first try going to Device Manager and see if there are any items with yellow exclamation marks there - and whether having the usb drive present or not makes a difference.

If so let us know.

You could also uninstall all the items from device manager's USB Serial Bus Controllers and reboot - unless that is what you said you did in your opening post. Presumably you dont move the drive from one port to another or use a different cable when booting to the two different installations.

Otherwise it would seem to be a windows problem possibly even some blocking by NIS or other firewall anti-malware application.

[kfh]

Hi Paul,

Yes there is a yellow exclamation mark in device manager, I unistalled the device rebooted with the device installed also disabled AV and Firewall. I've just removed SP2 and reinstalled it, the only thing left is I guess is a XP repair.

Thanks,

kfh.

[Paul Komski]

I have seen this happen on USB 2 boards where the basic motherboard chipset drivers were not installed or needed updating - even if WinXP is running SP2 (which should normally upgrade the USB to USB2 - but not if the basics were wrong in the first place).

You are running SP2 but do you have any USB PCI to Host controller specified as enhanced? If not reinstall the mobo chipset drivers and then if necessary reinstall all the USB devices. Windows can't identify the device if it is not sitting on the appropriate underlying layer of software.

[kfh]

Hi Paul,

I've just loaded the latest mobo chipsets, there is now no exclamation marks in device manager. But the drive is still not showing up in my Computer.

Thanks,

kfh.

[Paul Komski]

Try uninstalling all the USB entries in Device Manager and reboot.

If still not showing in My Computer check that whether it shows up under removable storage in Disk Management.

When you reboot do so with no USB device attached and only attach it when everthing has finished loading from startup.

[kfh]

Hi Paul,

Just tried that still no joy.

Thanks.

[Paul Komski]

I have two partitions on my machine, both Xp Pro SP2
Double-check that you have SP2 and check whether you have any USB PCI to Host controller with the word enhanced it.

Fraid otherwise I'm out of ideas other than repairing the OS or going back to a restore point if you have an appropriate one.

[Sylvander]

"Unknown USB Device"
When working in the Windows installation where this is the case...
1. Go to "Device Manager->[maximise the window]->View->Devices by connection->[highlight the PC symbol at the top of the tree]->hit "Numlock + *" [to expand the tree], then "Numlock" again [to reset Numlock back on].
2. Scroll down beneath "PCI Bus" to [something like] "USB Enhanced Host Controller" [see the image below].

3. Is there...
USB Enhanced Host Controller
___USB Mass Storage Device
______Generic USB Flash Disk USB Device
_________Generic Volume

4. And is it enabled and working OK?

5. Or is there instead an "Unknown Device" listed somewhere?

6. If all looks well in Device Manager, check that the same drivers are being used in both Windows versions.
If that checks, I go with an XP repair.

I hope a little added assistance isn't unwanted Paul. :)

[Paul Komski]

I hope a little added assistance isn't unwanted
There's no monopoly on help I trust ;)

However I would very much like to know if the word ENHANCED does appear because if so then USB2 drivers have been installed. USB2 drivers are installed by SP2. They can only be installed if the underlying chipset drivers and USB1 drivers have been correctly laid down first. Since USB-Drive Drivers are loaded natively by Windows, getting the correct drivers shouldn't have been problematic.

If device manager is showing no problems but there is mal-recognition of a drive known to work in another installation then most likely the port or its power supply is faulty (hence try other ports) or Norton's firewall (NIS) or similar could be blocking access.

Possibly the drive letter assignment has gone astray and so checking Disk Manager (Manage from RClick on My Computer) to see if the USB removeable storage device is seen there (but with no drive letter assigned to it) could be worth trying.

P.S. The unknown device in this case seems to have been the underlying chipset and not the drive per se and I had believed that problem to have been resolved.

[kfh]

Hi All,

(Manage from RClick on My Computer) I tried this on both partitions, the partition that the usb drive works on, has that drive listed under libraries along with my hard drive.

Thanks.

[Paul Komski]

I'm out of ideas.

[Sylvander]

"the partition that the usb drive works on, has that drive listed under libraries along with my hard drive"
Just as would be expected?
What is much more to the point is what is being displayed in "Device Manager".
Things aught to look the same for this device in both installations of WinXP, but probably won't.
What actually shows in the WinXP where the "Generic Volume" [the Flash Drive] isn't working, might point to the nature of the problem, and possible cause.

[kfh]

Hi,

This is what shows,

[Sylvander]

I take it that your displayed image shows your "Devices" displayed "By Type", right?
It would be better if they were displayed "By Connection", however...

THINGS I NOTICE
1. No "Enhanced Host Controller".
2. No "USB2 Root Hub".
3. No "USB Mass Storage Device".

When I display my USB devices "By Type" I too don't see the following [not listed under USB anyway] which ARE shown when displyed "By Connection".
4. No "USB Flash Disk".
5. No "Generic Volume".

Any idea what could cause that Paul?

Here's mine "By Type"...