You may have to reset or restart the phones when you make changes to the Cisco CME configuration. When a phone is reset, it goes through the entire bootup sequence. A phone reset is very similar to power-cycling the phone (powering it on and off). When a phone is restarted, it clears its current registration with Cisco CME and registers again. Restart is faster than reset. A restart is sufficient for configuration changes such as adding another line or speed dial to the phone. A reset is required for system-level changes such as upgrading a phone load or changing the URL for a directory search.
Cisco IP phones can be reset from a Cisco CME router console, from the Cisco CME GUI, or from the phone itself. A restart can be issued from the Cisco CME console or the Cisco CME GUI. You can reset or restart individual phones from the Cisco CME router console by issuing the reset or restart command, respectively, from the ephone configuration prompt.
You can reset from the phone itself by entering the key combination **#** from the phone dial pad. The phone should be in the on-hook state when you enter the key combination.
Erasing the Phone Configuration