Changing the System Time and Date must be accomplished from Extension 20 !
While on hook, press the Program button
Press the Down Scroll button until System Programming is displayed
Select System Programming
You will be prompted to enter a password. Enter 1 1 1 1 #
Select Time and Date
Enter the time in 24 hour format
Enter the date in MMDDYY format
Press Confirm or press the Speaker button to end.