USB device no longer recognised
I have a GoPro which was working fine on the Apple, I connected it to my sons Windows computer to edit some video, now when I plug it in to the apple it is not showing anywhere! Likewise the external hard drive I used on his computer to transfer the files is no longer recognised on the Apple.
I must be missing something? They are still there showing on the Windows computer.
OS X Mavericks (10.9.5)