Right then, searching for suggestions because there isn’t much coherent talk on the internet about this: I’ve got an issue right now where my Win 7 64-bit system is outright refusing to recognize any new USB device. All the ones plugged in at present are playing nice, but every other one I attempt to plug in (regardless of port) is “unrecognized” (including ones that I know work and have used previously on my system).
Thus far I’ve tried uninstalling/reinstalling the unknown device as well as detect hardware change to try and force a recognition and flashing my BIOS. My usb.inf file appears to be present and intact.
I reset my USB stack with USBDeview; things are working for the most part now (occasional problems, but nothing near as widespread as I was previously experiencing). I’m going to ride this (temporary?) fix for a bit and see what happens.