Please see the image below for key information.
The ringer may be silenced. Follow these instructions to restore the ringer volume to factory defaults.
Press the RIGHT DISPLAY BUTTON (labeled button #2 in the illustration below)
Press press the DOWN button (labeled button #10 in the illustration below) until you highlight HANDSET on the phone's display
Press the RIGHT DISPLAY BUTTON (labeled button #2 in the illustration below)
Press press the DOWN button (labeled button #10 in the illustration below) until you highlight RINGER VOLUME on the phone's display
Press the RIGHT DISPLAY BUTTON (labeled button #2 in the illustration below)
Press the UP/REDIAL KEY (labeled button #4 in the illustration below) until VOLUME 5 appears on the display.
Press the RIGHT DISPLAY BUTTON (labeled button #2 in the illustration below) to save the changes
Dial the phone's extension from a different handset to test your new volume settings