First of all, you have to enter the TES824, telephone exchange system by pressing the PROGRAM (programming) key, and then enter *#1234 into the system and enter the code 405 (hit the setup) and then press the SP-PHONE (next) twice to display the CO1:#01: Enable
CO1 stands for Outside Line Port 1
#01 stands for extension port 01
Enable stands for callable
Disable stands for unavailable
This time, Enable is the state of blinking and also the state of modification, press AUTOANS (select) to change port #01 Enable to Disable; unavailable CO1 outside line press STORE (save) in the press SP-PHONE; (next) jump to the CO2 outside the same as above to the # 01 port Enable to Disable; press STORE (save) and so on to the C04 to 8 are changed to the same can be.