What it means
The server recognizes the method but will not allow it here. The Allow header lists the methods it does accept. Common when a device sends INFO, UPDATE or OPTIONS that the far end blocks.
SIP/2.0 405 Method Not Allowed
Common causes
- The method is disabled by policy on the far end
- An SBC blocks OPTIONS or INFO even though calls work
- The device is using a method the server does not support in this context
How to fix it
- Read the Allow header to see what is permitted and use one of those methods
- If OPTIONS pings are blocked, that alone is not a fault and calls may still work
- Enable the method on the far end if you control it
See it in your own trace
Paste a full SIP or Asterisk log into the decoder and ladder tools to see exactly where this response appears in the call and what led to it. Everything runs in your browser, so your logs never leave your device.
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