Lexmark CX827
From the control panel
Press and hold the 5 key until you hear a voice message.
Select OK.
From the keyboard
Press Tab to navigate the focus cursor to the OK button, and then press Enter.
Notes:
Enable your printer to send faxes through the voice channel of a digital subscriber line.
Connect your printer directly to an active telephone wall jack or share a line with an answering machine or voice mail service.