Had a small problem with a KVM not working on a PC at a remote site today..

Connected remotely it came up as an Unknown device..

Checked the %SYSTEMROOT%\inf Folder for 0 length inf files..  Found one so that was deleted..   Then deleted all the %SYSTEMROOT%\inf\*.pnf files as well..  Any necessary one’s were recreated on the next driver enumeration.

Still no difference, so then opened the log %SYSTEMROOT%\setupapi.log, I then noticed the following lines
#-019 Searching for hardware ID(s): usb\unknown
#-018 Searching for compatible ID(s): usb\unknown

No matter what, the driver won’t install.. if it has this ID..

So must be hardware..

The device was restarted, that still didn’t work, so I got the user to try a few other ports…
That was it..

Stuffed Cable..