Solution
1. Press [Additional Functions].
2. Press [Left cursor] or [Right cursor] to select [5. TX/RX SETTINGS], then press [OK].
3. Press [Left cursor] or [Right cursor] to select [2. FAX SETTINGS], then press [OK].
4. Press [Left cursor] or [Right cursor] to select [2. USER SETTINGS], then press [OK].
5. Press [Left cursor] or [Right cursor] to select [2. TEL LINE TYPE], then press [OK].
6. Press [Left cursor] or [Right cursor] to select the telephone line type, then press [OK].
[TOUCH TONE]: Tone dialing (default)
[ROTARY PULSE]: Pulse dialing
7. Press [Stop/Reset] to return to the standby mode.