/mcpUnified CM database. If this is a third-party phone, confirm that the phone configuration is correct and matches the Unified CM configuration. If this is a Cisco IP phone, go to the Cisco Unified Reporting web page and confirm that database replication has a "good status" in the Unified CM Database Status report. You can also go to Real-Time Reporting Tool (RTMT) and check the Replication Status in the Database Summary page. If status shows 2, then replication is working. If the database replication status is good, reset the device. If the problem still persists, restart the TFTP service and the Cisco CallManager service from the Control Center - Feature Services web page. 3 MalformedRegisterMessage - Unified CM cannot process a REGISTER message because of a problem with the format of the message. If the device is a third-party phone, confirm that the endpoint is sending a properly formatted REGISTER message. 4 AuthenticationError - The digest User ID or password sent from the phone does not match the User ID or password configured in Cisco Unified CM Administration. Digest User ID is the end user who is associated with the phone, as shown on the Phone Configuration page (in the Digest User drop-down list 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 220/343