My PC can't detect my WD Passport Essential 500GB

I have recently purchased the captioned product on 30 Sept 2011.  However, yesterday when I tried to write a file to it, a message pumped up as “Window can’t recognize it and all the data is going to be lost”.  After then my PC can’t read it anymore.  I have phoned the HK agent (VST) for help, but they can only exchange a new one for me and can’t help to recover the stored data.  In fact, I have stored some very important data in the newly purchased WD drive and did not make any backup as I never know that the reliability of a WD product is so vulnerable.  Please help, otherwise I will definitely get fire from my boss.  Please!!!

Hello,

Try to use Photorec, this application will try to recover the data for you. 

http://www.cgsecurity.org/wiki/PhotoRec