Hi there bilal_282,
That is really unpleasant.
🙁
How does the HDD appear under Disk Management?
Basically, I would agree with atljsf. You can see if some data recovery tool would be able to access the drive, so you can back up the data stored on it.
Once your data is safe, you can test the drive, as Tesetilaro suggested. You can either run a brand specific testing tool, or test it with some of these:
http://www.tomshardware.co.uk/forum/282651-32-best-diagnostic-testing-utility
Look for pending/reallocated/uncorrectable sectors in the SMART report.
Keep in mind that this disk check function, sometimes, could result in data loss when there's something wrong with the drive.
Cheers,
D_Know_WD
