June 16, 2010

359 words 2 mins read

“USB Drive not formatted” on one computer, but fine in another

I was working on a friend’s computer this last weekend and I ran into a problem where her Kingston DataTraveler 16 GB suddenly stopped working on her Windows 7 Home Premium PC. My netbook, Eek, is currently running Windows 7 Ultimate and recognized it just fine.

This was only the start of the USB problems.

The original complaint was that the desktop couldn’t recognize a multimedia card reader (she was trying to offload some photos), which my netbook had no problem with. Next, I tried plugging in her

iPod Nano (1G) which both iTunes and Windows also claimed were not formatted correctly. Then I tried my iPod Touch (2G), which worked without a problem. Finally, I decided to unplug the working USB mouse and use its port to plug in “not formatted” devices. No dice, and when I plugged the mouse back in, it didn’t work any more. At this point, the only functioning USB device I had was the keyboard. So I rebooted, which gave me the mouse back, but still no luck on the other devices.


  1. Boot the machine with Windows 7 install disk
  2. Click ok/next on the first screen (asking about language and such)
  3. At the next screen, instead of clicking Install, select Repair.
  4. It will look for your install, once it finds it click Next then launch a command prompt.
  5. Plug in the USB device
  6. Navigate to it via command prompt (just keep trying drive letters till you find it).
  7. Once you are there, give it a dir
  8. If that works, try any other malfunctioning devices (I just did the card reader, didn’t try the iPod).
  9. Reboot.

Once Windows 7 boots back up, the devices (including the iPod) worked again. Huzah!

It seems that INFCACHE.1 may have been the culprit, I couldn’t find it to delete it while in Windows (it is supposed to be in C:\WINDOWS\inf), but I saw it from the recovery console and figured that it might be the cache generated by the recovery process, which was in fact working, so I left it on there (rather than deleting it, which was my first instinct) and now things are working great.