Computer cannot detect the external drive

I bought the 1 TB drive  last November  Model Number : S/N [edited] this I partitioned in to two 500 GB for Mac and 500 GB for window, It was workding fine till last few days and suddenly the computer has stopped recognize it , It shows the light on the disk, the disk  is not physically damaged. Does anyone has soln. for the same. 

Please guide. 



Did you tried checking if it was recognized on the disk utility app for Mac or the disk management for Windows?

I use my passport as an external hard drive to save my work to but today the computer is not recognising it instead it shows that the smartware drive is full can anyone help me to sort it as my life at work is saved to the passport drive and I never dowloaded smartware or set up an account I just inserted the drive into the computer and clicked on my passport and saved and opened files from there.

Hope there is help to retrieve my files



I also cannot retrieve all my files on my passport.  The light it lit but my computer does not recognize it as an external drive and I have all my son’s wedding pictures as well as everything else on there.

Any suggestions in retrieving the files would be most appreciative!