In this scenario, we are going to show you how to use the 3CX Server Activity Log to identify why a call to another extension is failing. In our scenario, the phone of the calling party shows "Forbidden" when the call is made, while the phone of the called party will never ring.

The procedure described below can be used to troubleshoot similar situations.

Proceed as follows:

  1. Ask the caller to reproduce the problem by dialling the same number.
  2. Load the 3CX Management Console, and click on the "Server Activity Log" node.
  3. At this stage, you have three options – filter by the called extension, filter by the extension making the call, or filter by the call itself. Remember that when filtering by one extension, in most situations you will have the logging generated by that extension.
  4. For this case, lets filter by the called extension (extension 101 in our example). This generates the following logging. Remember to start reading the logging from the bottom, up:

    Leg L:28.1[Extn:101] is terminated: Cause: BYE from PBX
    [CM503020]: Call(C:28): Normal call termination. Call originator: Extn:101. Reason: Forbidden
    [CM503016]: Call(C:28): Attempt to reach <sip:[email protected]:5060> from Extn:101 has failed. Reason: Forbidden
    [Flow] Call(C:28): Attempt to make call from disabled extension Extn:101 has been forbidden!
    [CM503001]: Call(C:28): Incoming call from Extn:101 to sip:[email protected]:5060
    NOTE: Endpoint Extn:101 is disabled by Admin

  5. The logging indicates that the called extension is disabled. The admin would need to re-enable the extension, otherwise the extension will not be able to receive any calls.

More information on the 3CX Server Activity Log and other examples on how this can be used for troubleshooting can be found here.