cd won't eject?

I tried putting a cd into the player when one was already in the machine. I had it in about 1/2 way before I pulled it out. Now the cd in the machine will not eject and will not play. I have hit the following buttons on the remote: eject, play, next track, previous track. I eventually get one of two messages: "Disc error" or "not playable". How can I get the cd out of the machine