You can configure Panasonic EPABX System KX-TES824 after fallow just few steps- Enter in programing mode then after you configure just 6 steps as given below- Steps-1 Enter the in programing mode Enter Code "000" Set the Date & Time according to Instructions Date & Time Setup[000] Steps-2 Enter the in programing mode Enter Code "009" Configure Extention Number as given below Plan in Note Extention Number Assigning[009] Note- Programeable number follow as below- Plan 1: 100-199 Plan 2: 100-499 Plan 3: 20-49 Steps-3 Enter the in programing mode Enter Code "121" Select "0" or "9" according you Automatic Line Access[121] Steps-4 Enter the in programing mode Enter Code "401" Select DTMF Dial Mode[401] Steps-5 Enter the in programing mode Enter Code "400" Select "Connect" for you CO Line Select "No Connect" for Blank CO Port