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Fax API - Error List

In this article find explanations for both outbound and inbound errors you might experience with Programmable Fax.

Dillin avatar
Written by Dillin
Updated over a year ago

Fax - Errors

Outbound Programmable Fax Errors

Error

Description

file_size_limit_exceeded

Error from Telnyx programmable FAX Application indicating the .pdf file provided is greater in size than the prescribed limits. (i.e. bigger than 50MB)

page_count_limit_exceeded

Error from Telnyx programmable FAX Application indicating the .pdf file provided is containing more number pages than the prescribed limits. (i.e. more than 350 Pages)

fax_signaling_error

Error from Telnyx Telephony Engine. Includes scenarios such as no response after sending a page, invalid ECM response received from receiver, received bad response to DCS or training.

file_download_failed

The non-telephony service responsible for downloading the customers PDF prior to initiating the fax was unable to download the file. Please make sure there are no redirect responses (3XX HTTP) only 2XX HTTP responses will ensure we download your file and process it.

file_format_invalid

The customer file format is not PDF or is invalid PDF.

receiver_call_dropped

Error from Telnyx Telephony Engine. The call dropped prematurely.

receiver_communication_error

Error from Telnyx Telephony Engine. Can include general call failure or a telephony routing error.

receiver_decline

Error from Telnyx Telephony Engine. The destination declined the call attempt.

receiver_invalid_number_format

Error from Telnyx Telephony Engine. The destination number is not in valid +E.164 format.

receiver_no_response

Error from Telnyx Telephony Engine. This cause is used when a called party does not respond to a call establishment message with either an alerting or connect indication within the prescribed period of time allocated.

receiver_recovery_on_timer_expire

Error from Telnyx Telephony Engine. Remote party sends a 408 for call expired or issue with downstream carrier partner.

receiver_unallocated_number

Error from Telnyx Telephony Engine. This cause indicates that the called party cannot be reached because, although the called party number is in a valid format, it is not currently allocated (assigned).

service_unavailable

Internal Telnyx error. A call to another service, such as to initiate the outbound call or to retrieve the PDF for sending failed. Could also be due to a non-typical media conversion failure.

success

Telnyx to investigate this further.

Retries for outbound faxes which may result in an error must be configured on the client application, Telnyx does not automatically retry faxes with errors.

Inbound Programmable Fax Errors

Error

Description

carrier_lost

Connection to carrier dropped while receiving the fax

fax_signaling_error

Error from Telnyx Telephony Engine. Similar to outbound error but in reverse. Includes scenarios such as no further data after receiving a page, ECM issue, bad data sent from sender etc.

received

Telnyx to investigate this further.

sender_call_dropped

Error from Telnyx Telephony Engine. The call dropped prematurely.

sender_canceled

Error from Telnyx Telephony Engine. The sender canceled the call prematurely or before data had completed transmitting.

sender_communication_error

Error from Telnyx Telephony Engine. Can include general call failure or a telephony routing error on the sender side.

Other Fax Errors Include:

  • account_disabled

  • connection_channel_limit_exceeded

  • destination_invalid

  • destination_not_in_countries_whitelist

  • destination_not_in_service_plan

  • destination_unreachable

  • invalid_ecm_response_from_receiver

  • no_outbound_profile

  • outbound_profile_channel_limit_exceeded

  • outbound_profile_daily_spend_limit_exceeded

  • receiver_incompatible_destination

  • receiver_no_answer

  • user_busy

  • user_channel_limit_exceeded

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