When I plugn in my new external hard drive, my PC doesn't recognise my iPod. How can I fix this?

I've tried relettering the drive, and that didn't work :( Is it something to do with changing the port number? When I go to device manager my drive doesn't appear under the Coms and ports section.When I plugn in my new external hard drive, my PC doesn%26039;t recognise my iPod. How can I fix this?
Try using a different USB port. Sometimes that will allow it. If it doesn't then you may only be able to use device at a time because those 2 devices may compete for the sam IRQ.When I plugn in my new external hard drive, my PC doesn%26039;t recognise my iPod. How can I fix this?
Maybe it is the plug some of them are always screwed up.