The hard disk (Toshiba 2.5'') does not respond! it appears on the PC screen with the names of the files stored into it. However, i cannot access any files, photo, word, or video. the hard disk does not even accept scanning!
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If the disk is only powered by USB, try a dual-power USB cable like this: http://www.amazon.com/Cables-TG-6Ft-Mini-B-Male/dp/B001... the drive may not be getting enough power to function properly. Make sure your drive has the correct interface for the cable, you may need a Micro USB instead of a Mini.
Next, take the drive out of the case, and plug it into a PC directly with a SATA cable, see if it will read the files.
If not, you can try to run a program to fix the file system, if possible, on the drive. http://www.cgsecurity.org/wiki/TestDisk Make sure you read over the directions to prevent wiping the whole disk by selecting a wrong option.