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SIPResponse codes

SIP response code reference

Every common SIP response explained in plain English, with the likely causes, how to fix it, and the related codes to check next. Start typing to filter, or open any code for the full page.

1xx Provisional

100
Trying
180
Ringing
181
Call Is Being Forwarded
182
Queued
183
Session Progress

2xx Success

200
OK
202
Accepted

3xx Redirection

301
Moved Permanently
302
Moved Temporarily
305
Use Proxy
380
Alternative Service

4xx Client error

400
Bad Request
401
Unauthorized
403
Forbidden
404
Not Found
405
Method Not Allowed
406
Not Acceptable
407
Proxy Authentication Required
408
Request Timeout
410
Gone
415
Unsupported Media Type
420
Bad Extension
423
Interval Too Brief
480
Temporarily Unavailable
481
Call or Transaction Does Not Exist
482
Loop Detected
483
Too Many Hops
484
Address Incomplete
485
Ambiguous
486
Busy Here
487
Request Terminated
488
Not Acceptable Here
489
Bad Event
491
Request Pending
493
Undecipherable

5xx Server error

500
Server Internal Error
501
Not Implemented
502
Bad Gateway
503
Service Unavailable
504
Server Time-out
505
Version Not Supported
513
Message Too Large

6xx Global failure

600
Busy Everywhere
603
Decline
604
Does Not Exist Anywhere
606
Not Acceptable
607
Unwanted
608
Rejected

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