Wow! Had no idea this was such a problem.
I have tried almost all of these things in one way or another but there are
certainly a few things I can try. I am really impressed with this list!
Thanks much.

Ron

"Anna" wrote:

>
> "Ron Carr" <RonCarr@discussions.microsoft.com> wrote in message
> news:17DD5C7B-A43D-41F3-97A3-5B4415E4B369@microsoft.com...
> > When I plug in a USB external disk drive, or a flash memory card, the
> > device
> > does not show in Windows Explorer. Disk management shows the disk drive
> > (not
> > the flash memory) but it has no drive letter and I cannot assign one
> > (Change
> > drive or path grayed out). I do have an E: drive which is evidently the
> > memory card port on my photo printer - never used. (I have 2 hard disks C
> > and
> > D, my CD and DVD are assigned P and Q).
> > Thanks for any help.....I threw away a flash memory card figuring it was
> > no
> > good!
> > Ron
>
>
> Ron:
> These USB non-recognition problems have been vexing all of us for some time
> now. We've become increasingly convinced that the relatively large number of
> problems in this area involving the non-recognition of USB devices that
> we've all been experiencing is an indication that there is something
> seriously flawed with respect to either the USB 2.0 specifications, possibly
> involving quality control issues affecting the manufacturer of these USB
> devices as well as supporting components such as motherboards and other
> USB-related components. Then too, we've become increasingly suspicious of
> the XP OS as it relates to its recognition of and interaction with these USB
> 2.0 devices.
>
> We have encountered far too many unexplained problems affecting
> detection/recognition of these devices and their erratic functioning not to
> believe that something is seriously amiss in this area.
>
> We continually encounter situations where a USB 2.0 device - generally
> involving a flash drive or USB external hard drive, will work perfectly fine
> in one machine and not in another. And, in far too many cases, we're unable
> to determine why this is so since we're unable to detect any
> hardware/software problem in the balking machine that would cause this
> non-recognition effect.
>
> Be that as it may, we've put together a more-or-less checklist for
> troubleshooting these USB non-recognition problems that (hopefully) may be
> of some value to you and other users encountering this type of problem...
>
> 1. Access Disk Management and see if the USB device is listed. If so, and
> there's no drive letter assigned, see if you can assign a drive letter to
> the device.
> 2. If the USB device is listed in Disk Management with an assigned drive
> letter, right-click on its listing and select Explore from the submenu.
> Hopefully, Windows Explorer will open and the device will be listed.
> 3. Connect the USB device *directly* to a USB port on the computer, not via
> a USB hub. Try different USB ports should your computer have multiple ports.
> 4. Avoid using a USB extension cable.
> 5. Try connecting a USB device (that does not contain an auxiliary power
> supply) to a USB port both before and after the boot operation.
> 6. Where a USB (or Firewire) external HDD is involved, access Device
> Manager, highlight the Disk drives listing and click on the Action menu item
> and then the "Scan for hardware changes" sub-menu item. Do the same in Disk
> Management > Action > Rescan disks.
> 7. Try alternate powering on/off methods. If the USB device contains its own
> power supply, try booting up with its power on, then try powering on only
> *after* the system has booted to a Desktop.
> 8. Try a different USB cable.
> 9. In the USB controllers section of Device Manager, uninstall all the USB
> controllers listed and reboot.
> 10. If the device in question is not a commercial USB external HDD but
> rather one in which you installed a HDD in a USB enclosure, jumper the HDD
> as Master (or Single if the HDD is a Western Digital disk). A number of
> users have reported that jumper configuration corrected their
> non-recognition problem. In my own experience it didn't seem to matter how a
> USB external HDD was jumpered. But it may be worth a try.
> 11. If the device in question is a USB external HDD, first check out the HDD
> with the hard drive manufacturer's diagnostic utility. If it checks out OK,
> and you can remove the HDD from its enclosure (without voiding any
> applicable warranty), do so and install the HDD as an internal HDD to
> determine if there are problems with the drive.
> 12. If the USB device is connected to a USB 2.0 PCI card, try changing the
> PCI slot to which it's currently connected to another one.
> 13. Access the website of the manufacturer of the USB device to determine if
> there's any firmware update or info re the problem you're experiencing or
> there's any possibility that the USB enclosure itself might be defective.
> 14. Determine from the manufacturer of your motherboard whether there's a
> BIOS upgrade affecting USB device recognition.
>
> A number of posters have reported they've found useful information re
> troubleshooting USB devices on this site -
> http://www.uwe-sieber.de/usbtrouble_e.html
> Anna
>
>
>