IMAC OS X 10.9.5 Does not recognize cd/dvd (ATAPI HL-DT-ST DVDRW GallN) player after update was downloaded
iMac (27-inch Late 2009), OS X Mavericks (10.9.5), Orig snow leop
Have you checked the web site for a new driver.
FIRMWARE UPDATE FOR INTERNAL SUPERDRIVE
This might help. If you haven't done so yet, try installing Apple's SuperDrive Firmware Update 3.0, which is on Apple's support site at http://support.apple.com/en-gb/HT201953 to see if that resolves it. Although it's not specifically for that problem, the firmware update seems to be important for making external SuperDrives work in Yosemite, and it is one step I used to get my SuperDrive to work in a USB external case when plugged into my MacBook Pro.
Please let us know either way, whether the firmware update helps or not in your situation
cd/dvd player stopped responding
