We have an MLX-20L and I am trying to change entries as people have moved into different offices. It won't let me edit the entries.

You are just trying to change names?

1. Press Menu.
2. Press System Program.
3. Press Exit or Start.
4. Press More or Right Arrow Key.
5. Press Labeling.
6. Press Directory.
7. Press Extension.
8. Dial the extension number that you want to administer.
9. Press Enter.
10. Press Drop.
11. Enter the label information for the extension number selected. (Remove the plastic covers from the line and feature buttons, and remove the white labels. You will see the letters “A-F” on the display and the letters “G-Z” on the buttons. Enter the new name of the extension. See note below.)
12. Press Enter.
13. Press Exit or Back.
14. Press Home or Exit to exit programming mode.