I have an external Western Digital 500 gb HDD and suddently it has stopped working. It shows up on the computer but it says 0 bytes used 0 bytes free. Ive done alot of research on the internet and found out that Testdisk should do the job. But after I've run Testdisk on the harddrive it says No partitions found when I tell it to analyze. I've tried several times and one of the times it went through a huge amount of files instead of the normal about 2 minute scan. This one time it had scanned just 2% after 4 hours so i cancelled it. What should I do now? I have also tried alot of those recovery tools, but none of them seem to be able to find the drive.