2003 expedition, radio says error

This is a common problem with the Ford (any Manufacturers for that matter) 6 disc changers.  The problem is, there is a disc that has moved from it's desired location.  The elevator can not move past that disc.  It is a pretty easy fix if you are at least slightly mechanically inclined.  you will need a set of Ford radio removal keys available for a few dollars at your local auto parts store.  You will also need a t-15 torx driver and a #1 Phillips screwdriver.  Prefferably a screwdriver with a very good tip.  If you get all that and want to give it a go, just let me know.

The radio removal keys may not be needed for that vehicle.  Are there 2 holes on each side of the face of the radio?

The same thing happened to my 03. I loaded the disk and it wouldn't load or eject. I ended up buying an Eclipse nav and putting it in.

You don't need keys, you have to take the dash face apart and you can un-screw the unit from the vehicle.