Children, please. Listen to Starbat. When in doubt, blame Bill Gates. USB cables the culprit? Oh, Please!
I got the dreaded DNR message. Read these posts. Tried the unplug trick. Heh.
Finally, I did a System Restore from back before trouble started. Plugged in USB drive. Everything good. Then - a second later - the Device Not Recognized balloon popped up!!!
Of course - WINDOWS UPDATE! Windows restored me to before the trouble, USB worked fine, Windows sensed I was behind on updates due to the Restore, went out and got the Update - USB failed!!
SO, yeah, I disabled Windows Updates ... Restored again ... All is fine.
F-ing Microsoft.