Common causes for SIP Extension Registration Failures


PBX version: all

Trunk Type: SIP registration


1.Extension/SIP trunk registration failure caused by the firewall

Symptom:Internally registration status always stuck in Registering or Register Failed.

Solution: Remove the IP address of phone from Blocked IP Address.


2. Improper port map on router

Symptom: Remote SIP registration failed.

Solution: Make sure the SIP port you map on router is proper. The default SIP port for PBX is 5060 by default.


3. The option Qualify has been disabled

Symptom: Remote extension try to register the PBX but get failure.

Solution: Enable the option Qualify on Edit Extension page.


4. NAT and Register Remotely option 

Symptom: The registration status on IP phone is registered, but on PBX side is not.

Solution: Enable the NAT and Register Remotely option on Edit Extension page.

More checklist for SIP registration failure:

Checklist for SIP extension registration failure

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