What model is the drive. I ask because I had a flash drive that contained its own software that it installed the first time it was used. Perhaps your drive did something like that. If it did, you may need to use that same software to remove the drive.
Process Explorer can give you quite a bit of info. If you right click, or maybe mouse over some of the items, it will show what is being run and why. You could list the processes started up, or use the snipping tool to take a picture and attach.