I got the reflash to work, but unfortunately it didn't fix the problem. It still fails the loopback test, and uploading a sketch won't work either, do you have some more things I could try or should I write this one off?
@gromain
If it doesn't take you driver, you could try doing it manually with hdwwiz.exe (in the start menu, search for hdwwiz and hit enter). Let me know how you get on.