Core Issue
This issue occurs when a user tries to log in to a phone configured for Cisco CallManager Extension Mobility and enters the user ID and Personal Identification Number (PIN).
Resolution
The Error 0 error message requires that you ensure the neccessary Cisco CallManager Extension Mobility services are running. To resolve this issue, verify that all Cisco CallManager services are running. If not, start the services. Refer to Control Center for information on viewing the status and to start and stop Cisco CallManager services for a particular server in a cluster.
For information on how to activate or deactivate services from the service activation web pages, refer to Service Activation .
For other related information, refer to these documents:
Problem Type
IP phones and other clients (Client registration, faulty IP phone, etc.)
Call control software (CallManager, CallManager Express, ICS7750, SRST, SS7 call agents)
Call Control
CallManager
CallManager Features
Extension mobility and services
IP Phones and Clients
IP phone error messages
Failure Type
Error message
Cannot login or logout
When Problem Occurs
During login or logout
After entering username and password
End Where Problem is Heard or Device Type Involved
IP phone
IP Phone Errors
Error 0
CallManager Versions
CallManager 3.3
CallManager 4.x
