So then I run "Unknown Device Identifier".
The ONLY device in the list that seems to resemble the problem device [its given name is IDENTICAL to the name used in "Device Manager" = "Universal Serial Bus (USB) Controller", and no other has a name even nearly identical] is shown in the image below.
The driver I have is for a "Mercury KOB-USB2V4 USB 2.0 I/O Controller Card".
["Mercury KOB-USB2V4" is the key to finding this]
I downloaded their latest driver from HERE , and ran the installer exe file, but it seemed to make no difference, so I'm wondering if the problem controller may be the older USB 1.1 controller that has nothing connected to it right now.
THIS hardware matches the the "VT6202" and description in "Unknown Device Identifier", but the page says that the drivers for this are included in Win2000.
Have I misidentified the problem device?
Is it actually the USB 1.1 that needs a driver?
Should I just disconnect the USB 1.1 card with its 2 sockets [I have made use of them at various times for things that don't need high speed]?