This document explains the recommended workaround for the Registration Rejected: Error DBConfig error message. You might receive this error message when the IP phone auto-registers to the Cisco Unified Communications Manager.
Cisco recommends that you have knowledge of Cisco Unified Communications Manager and Cisco IP Phones.
The information in this document is based on Cisco Unified Communications Manager 4.x and 7900 Series IP Phones.
Refer to Cisco Technical Tips Conventions for more information on document conventions.
Typically, a Registration Rejected: Error DBConfig message indicates an issue with unassigned directory numbers (DNs).
Complete these steps in order to overcome this error message:
Go to the route plan report of the publisher and search for all of the unassigned DNs. If there are any, delete those extensions using the procedure described in CallManager 4.x: Delete Unassigned Directory Numbers Configuration Example. This should take care of the error message.
Verify that Auto-registration Disabled on this Cisco CallManager is unchecked under System > CallManager > Server in the CCMAdmin.
Choose the respective Cisco CallManager group, normally the default, and verify that Auto-registration Cisco CallManager Group is checked.
Choose C:\Program Files\Cisco\TFTPPath and look for the xmldefault.cnf file. Open the file with Notepad, and make sure that the Cisco CallManager group is there. It appears as the IP address of the servers group at the beginning of the file.
Check to see if a Certificate Trust List (CTL) is used.
Check for any replication issues.
If Cisco IP Phones cannot register to the Cisco CallManager with the Registration Rejected Database Config Error error message, and if the DBLHelper shows no issues with the replication, it might be due to the blank hosts file and lmhosts file. Make sure that you enter the required information in these files followed by a factory reset on the IP phone in order to resolve the issue.