From extension 300, dial #TD (#83).
Do this without lifting the handset or pressing any other keys first.
Enter the time in 24-hour clock using hours (2 digits), minutes (2 digits)
and seconds (2 digits).
Press HOLD.
Enter the date using month (2 digits), day (2 digits), and year (4 digits).
Press HOLD, then SPK to exit.

 

On any ESI phone within the system, press PROG/HELP. The normal station
programming menu prompt will begin to play.
Stop the prompt by pressing HOLD (or, on an older ESI phone, PARK).
Enter the Administrator password 456 and then press # Note: If this doesn't
admit you to Administrator-level programming (the phone display should show
ADMINISTRATOR), contact your ESI Reseller for assistance.

Access Function 14 by pressing 1 4.
(If the system prompts you to press 1 to set time and date, do so.)
Enter a new time using a twelve-hour format and then press #. Example: Enter
1 2 3 3 # for 12:33 or 3 1 5 # for 3:15 (note that you need no leading zero
for the time).

Select AM or PM by pressing a scroll key and then #.
When the date appears, either:
Press # to accept the currently displayed date as correct;
or
Enter a new date in an eight-digit format, including leading zeroes, and
then press # and hang up to finish the entry.
Example: For March 14, 2007, enter 0 3 1 4 2 0 0 7  # (and, to repeat,
leading zeroes are required here, unlike in Step 5).

 

At extension 10 or 11 press the Feature button, then dial number 0 twice, then using the two ICM keys (ICM keys are located underneath the Line1 and Line2 keys) press the left ICM button twice, then dial # 103, and the display should prompt you for time, at that point enter the time in 2 digit 24hr format (ex. 0830 for 8:30am) then simply lift your handset and hangup.

 

At any display phone press the Feature key then dial #, * (star) then

press the # key eight times, press show, then dial 0814, then press save, then press show, then press the next button 4 times repeatadly, Hour appears on the display, then press change, then enter the new hour in by dialing the time in 2 digit format (ex. 08 for 8) then press save after the time is entered, then simply lift the handset and hangup.

 

At any keypad press *(star) 6 then the master code (generally the main code)

then press 1 then enter the new time 2 digit 24hr format as follows, enter hour first, then minute (ex. 0830 for 8:30am) then press #  button twice to exit.