erm none atm,i have nero on disk but when i put it in the drive it shows a loading symbol on my cursor but then nothing happens whereas before it would auto run,i click my computer and its says the dvd drive F

here it reads the disk name) but when i click it it runs and says error could not read disk,then something about a cylic redundancy check. so the drives are installed but just wont read anythng? ive gone through device manager and uninstalled both of my drives then reinstalled them but theres still no difference?plz help im stuck.