External hard disk is not accessible how to access it

[yhsmurthy]

Hello,
when i tried to browse my seagate hd, it pops you have to format your drive before using it, and says not accessible, how do i solve this problem.

 

[nhasian]

TestDisk, Data Recovery
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PhotoRec is file data recovery software designed to recover lost files including video, documents and archives from hard disks, CD-ROMs, and lost pictures (thus the Photo Recovery name) from digital camera memory. PhotoRec ignores the file system and goes after the underlying data, so it will still work even if your media's file system has been severely damaged or reformatted.