I'm running Windows 7 via Boot Camp on an iMac.My dvd/cd drive works fine on the Yosemite/Apple side of things.
However, on the Windows 7 side of things it is as if the internal drive doesn't exist. There is no D:\ drive, nothing visible in device manager, etc. I've tried the windows Fix It tools and tried deleting the upper and lower filters in the registry (but didn't see those registry values).
My one moment of hope was after I reinstalled all of the Boot Camp software, including drivers, etc. On the first restart after installing that software, my dvd-drive was visible. I inserted my disk, and my computer froze. After restart it had disappeared.