Help! My Macbook Pro was restored to factory settings at the Apple Store as it had a few problems. This was fine because i had backed up all my data using an external hard drive with time machine. However I plug in my external hard drive to put all of my files back on my laptop, but the hard drive doesn't show up on the desktop or finder. It does show up in Disk Utility but it says I have no files on it. I defiantly backed it up the previous day, there should be over 300 gb on it. I plugged it into a PC to see if it works on there but it didn't show up on windows either. The only thing i thought it could be is the Partition format for the external hard drive is Mac OS Extended and the Mac hard drive is Mac OS Extended. Could this be the problem? Any help would be much appreciated!