Feature 3 will tell you the software version. Feature 4 will give you that set's port number.
Feature - Hold - #0* on port 1 or 2, Feature #0*8974 on other ports to enter programming.
Press line key 4, use * to back up to port number, enter port of telephone to program (2 digits). (01/01 = tel port/program #)
"01/01: Day Rng |1" The |1 is a page number.
A page is the first 8 line keys.
Press Recall to change pages until you get to CO 25 (3 times CO25 will be line key 1 at this point).
Press line key 1 until it turns green. Press Transfer to save changes. Press Speaker to exit. That should do it.