PC wont read external hard drive

Hi! I have a toshiba laptop and i bought a portable external hard drive everything was working fine. I backed up everything on my external drive before i restored the LpTp. Everything worked ok until just recently i plugged in the external drive and the drive shows that it is on. It is emitting its normal smooth running sound. but my computer wouldn't read it. I have yet tried to plug it in another computer but it seems like the problem might be my laptop since the drive seems fine what are my choices, how can i reset my USB ..when I go to the device manager I don't know which one is which.. someone please help.. Thank you J!!