Extension Dial Ring/No Ring option:  FEAT + 6 + 5 (this will turn on and off the beep or ring option when someone calls from another extension.) 
Turn the MIC on:  FEAT + 6 + 1 (If a button for MIC is listed that light will turn off indicating the MIC is usable)
Turn the MIC off:  FEAT + 0 + 6 + 1 (If a button for MIC is listed that light will be turned on indicating the MIC is disabled.)

Reception Desk Extension Notification of e911 call can be reset only at the District Office Receptions Desk. The top row 3rd button labeled CLR will clear the Notification from all Reception Desk phones.