Faxes can fail for a variety of reasons, such as sending to a non-working or non-fax number, a recipient listing their number on the National Do Not Call List, a recipient line being continually busy or out of paper, noise or interference on the line, or provider-side routing issues. Kno2 retries faxes a minimum of 5 times. If a released fax has a 'Failed' status, you can hover over the status for more error details.
Additionally, fax failures can also occur when attempting to send to non-fax line recipients, such as Direct addresses, making the transmission process incompatible.
Verifying a Fax Number
You can verify that the number is a working fax line by dialing it and listening for a fax tone. A few indications the line is having issues include:
The call receiving a busy signal.
The call ending before a connection is made.
The call ringing without ever connecting.
The call being answered with an "out of service" message.
The call being answered by a reorder tone (fast busy signal) indicating technical issues.
The call being answered by a person, auto-attendant, or voicemail.
Attempt a test fax or call to confirm whether the line has issues such as noise or interference, which are technical in nature and can impede successful connections.
If you encounter consistent failures to a 'good' fax number, please ensure you are utilizing Default as the Caller ID number. This is common number for the outbound Caller ID to improve deliverability.
Best Practices for Avoiding Fax Failures
Verify that all recipient contact information, including fax numbers , is accurate.
Perform test faxes, especially when you anticipate potential issues with the recipient line.
Maintain open communication with recipients to resolve any contact-related inconsistencies.
Utilize Kno2® troubleshooting resources for additional guidance when required.
If you need more information about a fax failure to a good number, please reach out to us in chat or at support@kno2.com and provide the following details:
The URL of the failed fax.
To obtain this, open the failed fax in Release and copy the message URL from the top of the browser to share with us.
URLs look similar to this:
If the URL is not available, provide the following information for two failed faxes for each failing number you wish to have reviewed:
Date (must be within the last 24 hours)
Time
To number
From number
Failure reason, if available
Need to retry a failed fax to a good fax number? You can Forward a Sent Message to send your original attachment again!