Use the Do Not Disturb or Silent modes when you are not available to take calls and wish to not be bothered.
Do Not Disturb
You can activate or deactivate the Do Not Disturb mode on a per-line basis.
When DND mode is activated for a specific line:
- All incoming calls to the line will be rejected automatically.
- Callers will hear a busy tone.
- The handset's screen will display the missed call icon (
) followed by the number of missed calls.
To activate DND for a specific line:
- Press
to enter the main menu and select the Call Features option (
on the 73H/78H or 
on the 56H). - Select Do Not Disturb. The lines currently assigned to the handset are shown, with the default line highlighted.
- Select the desired line and press OK.
- Use the left/right arrow keys to enable DND.
- Press the Save soft key to accept the change.
The 
icon on the status bar indicates the DND mode is activated.
You can press the Line soft key when the handset is idle to see the lines that DND is applied to as indicated by icon.
DND is also configurable via the web user interface at the path Features>Forward&DND.
Silent Mode
Silent mode is another option available to you when you do not want to be disturbed. In Silent mode, the handset will not ring when receiving an incoming call, but it will still display the incoming call information.
Switching on Silent Mode:
- Long press the
key until the phone prompts “All Ring Tones Off”. - The silent mode icon (
) appears in the status bar.
Switching off Silent Mode:
- Long press the
key again until the phone prompts “All Ring Tones On”. - The silent icon mode disappears from the status bar.