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SIP response codes

SIP 500 Server Internal Error

Server Internal Error: the server hit an unexpected condition while processing the request.

500
Name
Server Internal Error
Class
5xx · Server error
Defined in
RFC 3261
Q.850 cause towards the PSTN
41 · Temporary failure
Produced from Q.850 causes
111, 127

When it happens

  • A bug or misconfiguration on the PBX or carrier platform.
  • A database or script error in the dial plan.

What to check

  • Check the logs of the server that answered; if it is a carrier, send them the Call-ID and time.

What the response looks like

SIP/2.0 500 Server Internal Error
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
Reason: Q.850;cause=41;text="Temporary failure"
Content-Length: 0

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