driver not found

hi guys, i m new with arduino n got a problem, i hope someone can help me. my arduino mega 2560 cant be identified n the driver cant be installed by windows 7 eventhough i copied arduinomega2560.inf to folder driver in arduino1.5.2. i tried to change cable and another arduino, the result was same. 6 month ago everything is ok, i dont want to format hard drive. pls give me your suggestion, thanks before.

Hey,I'm more newbe than you. I bought a uno off ebay that I tried 3 windows xp computers, 1 vista, and finally got it to load in windows 8 laptop as a arduino mini- not an uno. A horrible clone from who knows where. So if its not an Italian board, good luck. I thought I'd get in cheap to see if I liked working with the arduino. I also bought a clone 2560 and it seems to work OK. I think when I get the working clone programmed, I'll go and get an official 2560, just to support the people who started the whole thing.