iPod not restoring on laptop as iTunes is not recognising it

My 120GB iPod classic suddenly erased all its content when I was listening to my music. It displays the message "Use iTunes to Restore", however when I plug it into my laptop; iTunes is not recognising it so I therefore cannot restore it. I have downloaded the lastest iTunes software version and have tried restarting Apple Mobile Device Support but nothing is working! Please help 🙂