For analog (non-IP) phones, use the following codes to access desired feature:

*50 = Disable Call Waiting (for all subsequent calls)

*51 = Enable Call Waiting (for all subsequent calls)

*67 = Block Caller ID (per call)
Dial *67 +  number (no dial tone will play in the middle).

*82 = Send Caller ID (per call)
Dial *82 + number (no dial tone will play in the middle).

*69 = Call Return Service
Dial *69 to call back the last incoming phone number received.

*70 = Disable Call Waiting (per call)
Dial *70 + number (no dial tone will play in the middle).

*71 = Enable Call Waiting (per call)
Dial *71 + number (no dial tone will play in the middle).

*72 = Unconditional Call Forward
Dial *72 and then the forwarding number followed by #.
Wait for dial tone and hang up (dial tone indicates successful forward)

*73 = Cancel Unconditional Call Forward
To cancel “Unconditional Call Forward”, dial *73, wait for dial tone, then hang up.

*74 = Enable Paging Call
Dial *74 and then the destination phone number you want to page.

*78 = Enable Do Not Disturb (DND)
When enabled all incoming calls are rejected.

*79 = Disable Do Not Disturb (DND)
When disabled, incoming calls are accepted.

*90 = Busy Call Forward
Dial *90 and then the forwarding number followed by #. Wait for dial tone then hang up.

*91 Cancel Busy Call Forward
To cancel “Busy Call Forward”, dial *91, wait for dial tone, then hang up.

*92 Delayed Call Forward.
Dial *92 and then the forwarding number followed by #. Wait for dial tone then hang up.

*93 Cancel Delayed Call Forward.
To cancel Delayed Call Forward, dial *93, wait for dial tone, then hang up.

Flash/Hook
Toggles between active call and incoming call (call waiting tone). If not in conversation, flash/hook will switch to a new channel for a new call.

# = Re-Dial
Pressing pound sign re-dial last number called.