my external hard drive was working fine last night when i was watching a movie that was on it but when there were about 10 minutes left to go it suddenly stopped. now my hard drive does not appear under "my computer" any more in windows xp, nor does it appear in disk management. when i connect it to my mac it tells me that the disk cannot be read and i have several options (initialize / eject / etc.)... it shows up in disk utility and tells me that it is unformatted. i purchased drive genius and made a duplicate copy of the hard drive. whenever i try to open the .dmg file, it tells me that the image file failed to mount because there are no mountable file systems? what does that mean? if i try to format it in disk utility i get a input/output error. if i try to format it in drive genius nothing happens. when i tried to scan it for hardware problems in drive genius all of the blocks that were scanned were bad blocks. what are my options? is the .dmg image i made usable?