Okay, this is my 3rd problem. So, I've figured out why it doesn't mount. I downloaded all of my files to it (40GB) and it worked fine. a day later, I added 1 file, and it wouldn't mount. I went crazy, I made a thread with no reply, I didn't know what to do. so I plugged it into a PC and it read it, and I deleted the last file I put on. I plugged it back into my mac and it worked. So, I used it for a few hours, then my friend send me a picture and I put it into the hard drive, and I restarted my computer and again... it didn't read it, so once again i plugged it into a PC, deleted the file and it works... My question is, why is this happening? and how can I fix it... without formating it. Any help would be great. Once this is fixed, I hope I won't have to make a thread about it again. I spent $200.00 andi've only had it for 3 days, and I have had to make 3 threads. Thanks.