My partition volume is showing in the My computer

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@Afta...
What type of drive are you using? I had the *EXACT* same issue on WinXP w/Seagate.
I could see the drive everywhere EXCEPT explorer. (Disk management/etc)--Even 3rd party tools.
However,when trying to access the drive, would error out with the need to Format Drive.
Thus drive completely inaccessible. "Dead" (support codes/support confirmed this).

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If you are using Seagate, go to their site and look for "SeaTools"

Here is te ROOT URL: http://origin-www.seagate.com/
(of course you'll have to click deep for your configuration).
SeatTools runs a series of Tests to determine if you can recover the Data. If you cannot, SeaGate will send you a replacement disk or you can use their Data Recovery Services.

*IF* your Data is that important, their Pricing (to me) did not seem out of line (started at $99US).
Based on the Error codes I received. I emailed support the codes. Support said the disk was unrecoverable (with their tools on my end) I simply replaced the drive.
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I can only speak to Seagate, however I assume other Manuf. WD/Samsung,etc. Have the same process.

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PS--If you Google around (my apology, I honestly don't remember the website)--however you can Find (FBI level) "forensic recovery tools" (I found them when trying to recover my Data). I seem to remember it was typical nonsense..they only allow you to see ridiculous..like 500MB! (then pay $$$-for the Software).

PPS--I just thought of this. (if the Data is that important, you want to try to recover yourself).

I did a Google Search for

inurl:gov Forensic Data Recovery Tools

IF you look at FBI sites/Secret Service,etc.
http://www.ncfi.usss.gov/catalog.html
BCERT---Basic Computer Evidence Recovery Training

You will find "course catalogs"---I *BET* they will list (as part of Syllabus,etc.)--The Book/Tools you need. (??)

The Forensic Tools I found were some "National Association of...." Type of
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LAUGHING!!! (hey, I always try to find a laugh in the midst of crisis..I'm not laughing at your problem.
Trust me, I know your Panic/Distress. However, posting this made me curious enough to start to dig a little bit.

For all the "conspiracy nuts" there is a PDF/"White Paper" on Facebook Forensics..
I guess the F.B.I. is watching after all....
https://www.fbiic.gov/public/2011/jul/facebook_forensics-finalized.pdf

ps--found this looking for something else (if you don't have Seagate/desire other tools before returning).
http://www.howtogeek.com/134735/how-to-see-if-your-hard-drive-is-dying/

"Use CrystalDiskInfo" (name of application).