Mitel 5550 IP Console - Manual (Page 81)

Reference ♦ 75
Unassigned Directory Number
The number you dialed is not recognized by the telephone system.
Verify your number and try again.
Wake-up Call Not Acknowledged
Part of the Hotel/Motel Feature package. The guest has not answered
the automatic wake-up. (Note: The Hotel/Motel package is an optional
feature.)
Wake-up Call - System Error
Part of the Hotel/Motel Feature package. The Wake-up function is not
operating properly. Contact your communications department.
You are already using the selected language. Language not changed.
You made a mistake in selecting the language. Repeat the procedure.
Telephone Directory
Name Number