Windows 7 - External HDD detected but doesn't show up in explorer

I have a WD 500GB external hard disk. It had been working fine on any computer systems that I used it on, for more than 5 months and all of a sudden it is not shown in the My Computer window. But it is still detected and installed correctly on any system that I plugged it into.

Here is a screenshot of diskmgmt. It says the disk is unallocated.



Any ideas how to solve this problem?

P.S. I already tried rebooting in safe mode, and rebooting again in normal mode. It didn't help. Also I have read many posts with similar problems but they do not exactly match my problem scenario and weren't of any help either.

I don't see a screenshot...
How is it reported in Disk Management ? ?
If it says RAW it's been unplugged prematurely too many times.

It will not show up in My Computer as its unallocated space. The question is, is there anything on that drive at present, if not then just create a partition and it will show up in My Computer - Partition or Volume - Create New

However if there was/is data on that drive do nothing until you seek some further advice here.

Danny

Its not a new one and there is a lot of important data on it. Guess I will have to wait.

Ok if there is important data on that drive just hang on.I will ask for one of the experts in this area to drop in and have a look for you.

Danny

Check out this excellent suggestion from member jumanji in this thread:
Western Digital drive showing up with Unallocated in disc management

One of several excellent solutions found by using the search function in SevenForums!

Install free Partition Wizard to see if it detects the drive's partition instead of just unallocated space.

If so, rightclick on it to Check File System which can correct errors to restore the HD. If necessary assign a drive letter if the partition is missing it but do not create a new partition to do so.

If it shows as Unallocated Space in PW then click on HD to highlight it and from Wizards tab select Partition Recovery Wizard, have it scan the HD to see if it can recover it's partition intact, if so tick the box and Restore it.

If this fails post back a screenshot of PW. You may need to use Recuva to try to resurrect the data.

I tried jumanji 's procedure but it didn't work. Test disk did not detect any partitions on the HDD even after a long scan.

I tried to initialize the HDD in disk management but it gave me an error msg saying "media is write-protected".

What could be the reason for this problem? The HDD had been working fine for a long time.

Could this be due to a damaged USB cable?

Do not try to initialize the HD as it will destroy the data.

I gave you the steps to try to fix or recover the HD's partition or it's data.

I tried the steps. PW detected the hard disk as a bad disk and when I right-click the HDD none of the options are available on the pop-up menu.

Here is the screenshot of PW: