My Passport not recognized

I have had an WD My Passport for a while now And I recently tried to boot another computers OS from before I even did that All I had done was transferring The files to The Passport, then it stopped working as an Harddrive. Now I can find it in devices And it says everything is fine but I can’t use it as an harddrive it is not showing up at All. All I see is my standard harddrive. The drivers is also showing up So I have really no idea why this would happen. And The passport is showing up on my friends PC we both have laptops And windows 8.

So I have no idea why this would happen any ideas?

Try running a test with DLG. 

http://wdc.custhelp.com/app/answers/detail/a_id/940