Connection of external harddrive

I have Gen 2 and WD live  media players which I have had for a number of years

In the last 12 months I have purchased 3 external hard drives the most recent a WD Elements 3TG

and before that a WD My Book TG . These models have been prviously recognised by the media players

Yet now the new ones are not. My firmware is uptodate and the WD Live player is only 6 months Old and is working on other external drives Any suggestions as to fix the problem

Plug them all into your PC and scan them for errors.