/mcpappropriate phone model to learn how to access the phone logs), and contact the Cisco Technical Assistance Center (TAC). 18 The phone did not receive a load server name or IP address and as a result, does not have the server information needed to download a configuration file. Check the Device Configuration page in Cisco Unified CM Administration to ensure that the IP address of the Load server or TFTP server is accurately configured. If the information is inaccurate or not present, supply the correct information and restart the phone. If the information is accurate, restart the phone. If this alarm recurs, contact the Cisco Technical Assistance Center (TAC). 19 The DNS server name that the phone is attempting to connect to could not be resolved. Examine the DNS server name(s) in the phone settings to verify that the information is accurate and if not, update the name on the phone. Restart the phone unless the restart occurs automatically. 20 An internal phone error occurred in processing the configuration file; restart the phone to correct the issue 21 Configuration file Re-TFTP - Phone need to download the configuration file again. 5/24/26, 3:34 AM System Error Messages for Cisco Unified Communications Manager 15 - Cisco https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/err_msgs/15_x/ccmalarms15.html 321/343