My lapton is not recognizing my 3tb WD external

I bought a 3tb WD external and was planning to transfer some items from my 600mg WD external (that I love) through my laptop to the new drive. I got it to work  once, and was able to transfer a few things, but when I went to move over a few more things my laptop will no longer recognize the 3tb drive. I don’t get an error message, it just acts as if there is nothing there.  I have tried changing the USB, as well as the port, and have also rebooted my laptop a couple of times. The light on the 3tb just sits there and blinks at me, any ideas? I would greatly appreciate it. Thanks!

Hello,

Is the drive connected to a power strip or directly to the power outlet? Also have you test your drive in a different computer?