Mounting Media failed : no medium found on /dev/sr0 while installing package

I am trying to install packages like gcc-4.7-7.1.1.x86_64.rpm and some more error shows no medium found on /dev/sr0 and installation gets stop please help how fix it.
Thankyou

YaST > Software > Software Repositories.

Select the repo which start with something like cd://. Uncheck the Enable box below and OK.

That should fix it.