Cd/DVD drive not reading discs

I have an Acer Aspire 5100 with a slimtype DVD A DS8a1p ATA Device. The dive had worked previously but I can not remember that last time before today that I put a cd or dvd in the drive. The Cd drive will not recognize any disc I put into it. Even when I click on the drive when ther is a disc in the tray it does not see one. I check the driver updates and the laptop says they are up to date. What do I need to do to get the cd/dvd drive to work again