After installing a Cisco Unified IP Phone into your network and adding it to Cisco Unified CallManager, the phone should start up as described in the below URL:
http://www.cisco.com/en/US/docs/voice_ip_comm/cuipph/7960g_7940g/4_2/english/administration/guide/7900ins8.html#wpxref54238
When you connect a Cisco Unified IP Phone into the network port, the phone should go through its normal startup process and the phone screen should display information. If the phone does not go through the startup process, the cause may be faulty cables, bad connections, network outages, lack of power, and so on. Or, the phone may not be functional.
