SIP 404 Not Found and 484 Address Incomplete

What the codes mean (general SIP)

• 404 Not Found — the server could not find the requested user or number; on a termination trunk this usually means the dialled string did not match any route.
• 484 Address Incomplete — the number has too few digits for the destination.

Common causes

• Number sent in national format (with a leading 0) instead of international format (country code first).
• Extra international access digits such as 00 or 011, or a "+" the trunk does not expect — or the reverse.
• A required tech-prefix missing, or one being sent to a trunk that does not use it.
• Dialer dial-plan stripping or adding digits unexpectedly (for example a VICIdial carrier dialplan entry that strips the first digit).
• Genuinely invalid or unallocated numbers in your list.

How to diagnose

• Look at the Request-URI of the failing INVITE in a SIP capture — that is exactly what the trunk received.
• Compare it to the format given in your trunk details and to the published prefix for the destination.
• Test one number you know is valid, dialled manually from the dialer.

At CallCenterBoost

Published rates are listed per dialling prefix in international format, as shown in the rate explorer. The exact number format and any tech-prefix for your service are confirmed during provisioning — if the format in your service details is unclear, ask in a VoIP Route ticket rather than guessing.