Right, here's the history of this horrible mess.....
My PC Is a Dell Dimension 2350
OS : Windows XP Home Edition , Version 2002 , Service Pack 2
My PC doesn't recognise any Plug N Play USB Devices. I initially had the problem with an external HD - but eventually got that resolved by placing the original XP CD into the PC and doing a search on the disc for driver.cab , copied that folder from the CD into a folder in the C drive called i386 and then reinstalled the HD manually by pointing the New Hardware Wizard to i386 to search for the compatable driver.
Then I had the same problem with a 1GB Flash Drive - The PC gives me littles beeps noise , so it's recognising "something" has been plugged it ... then when I go to My Computer - it's not there , so I do "Device Manager" and it shows listed as "Flash Drive" with a big yellow "?" and says No Driver - blah blah.
So I asked for some advice on another forum ... and was told to do this :
1. Plug the drive in and wait for it to go through the hardware not recognized steps. Keep it plugged in.
2. Click Start -> Run
3. Type regedit and click OK
4. Go to HKEY_LOCAL_MACHINE\SYSTEM\ControlSet002\Enum\USB
5. You will have to search through all the sub-folders here, looking for the name of your flash drive.
6. When you find it, make note of the flash drive name and delete the first folder where you find the name of the drive. The whole folder.
7. Do a search through the registry editor for other references to the drive and delete the rest of them.
8. Remove the drive from the USB port, reboot, and try to plug the drive in again after the system reboots.
This fixes about 90% of such problems.
Did that and now my WD External HD has disappeared too ... nothing plugged into a USB port is showing as recognised if it's Plug N Play !!! aarrgghhh
And Im no longer getting the beep noises when I plug in a Plug N Play device .... so it's actually worse than before !!
Help - please !!!!!!!!!!!!!!!!!!!!!!!!!