OS X El Capitan, Version 10.11.1: Disc utility is changed. Erase button is inactive.
After installing OS X El Capitan, Version 10.11.1 on MacBookPro 15, Disc utility format is changed. It is not functioning. Erase button is inactive to erase rewritable DVD.
MacBook Pro, OS X Mavericks (10.9.1), MacbookPro 15", 2.66 GHz intel core