Unhappy [Q] HELP! N7 Bootloader is USB\UNKNOWN in Win7x64

I'm trying to update my wife's N7 to 4.4.2 It's on 4.3 JWR66Y right now. Followed instructions here to get it there before. All attempts to upgrade right now have failed so I was going to try to use those directions again to get back to stock. Unfortunately now when I plug in to USB and enter the bootloader I get USB Device Unrecognized. The Hardware/Device ID is "USB\UNKNOWN" so I can't even load a driver! PLEASE HELP! I need access to fastboot!
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