Chappy

Hi Dave

Vista should have the natve drivers this external drive needs to be recognized, so it shouldn't need an updated driver.
It seems that for some reason, Vista just "burped" when trying to initialize this external drive and it's not fully operable. Have you tried unhooking the drive, then reboot without it, then shut down, hook up the drive and reboot again?
Or try hot-plugging (unplug & plug in while booted) it and see if Vista can recognize and install it properly again?

There is also an option in the Disk Mgmt applet to "Rescan Disks", open Computer Mgmt - Disk Mgmt, click Action - Rescan Disks, you can try that too.

I had an internal drive that was doing just about the same thing you're experiencing and it worked itself out after I played around with unhooking it, rebooting, powering off and hooking it up again, then rebooting. That usually fixes any problems when the system has trouble with recognizing and installing hardware properly, as long as it's not a case of failing hardware.