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SIP response codes

SIP 606 Not Acceptable

Not Acceptable: the user’s devices cannot accept any version of the call as offered.

606
Name
Not Acceptable
Class
6xx · Global failure
Defined in
RFC 3261

When it happens

  • No common media at all across the user’s devices.

What to check

  • Compare the offered codecs and media types with what the callee supports.

What the response looks like

SIP/2.0 606 Not Acceptable
Via: SIP/2.0/UDP 203.0.113.10:5060;branch=z9hG4bK776asdhds
From: <sip:101@pbx.example>;tag=1928301774
To: <sip:+15551234567@pbx.example>;tag=a6c85cf
Call-ID: a84b4c76e66710@203.0.113.10
CSeq: 2 INVITE
Content-Length: 0

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