SIP 403 Forbidden
FreeSWITCHRFC 3261 §21.4.4The server understood the request but refuses to authorize it. Often caused by IP ACLs, blocked numbers, or trunk billing checks.
Common causes on FreeSWITCH
- Trunk source IP not in allow-list
- Caller ID stripped, blocked, or not provisioned
- Outbound dial plan rejected the destination
- Account out of credit / suspended
FreeSWITCH-specific note
Check `acl.conf.xml` and the profile's `apply-inbound-acl`. FreeSWITCH also returns 403 when challenge-response auth fails three times by default.
Stop guessing — paste your trace
Drop your PCAP or sngrep log and SIP Flow will render the ladder, surface the failing transaction, and (optionally) ask Gemini to suggest the fix grounded in FreeSWITCH docs.
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