Watch Video

Using a virtual fax machine is an easy, convenient way to send faxes without needing an additional number or device (learn more about sending virtual faxes). When you know what to look for, e-faxing issues are usually a simple thing to diagnose and resolve.  Below are the most common types of errors and their solutions.

Access code is invalid

Cause
Access code was entered incorrectly.

Solution
Verify access code and resend.

An error occurred during conversion

Cause
The attached file is password protected.

Solution
Remove password protection and resend.


Cause
The attached file type is not supported.

Solution
Convert the file to a supported format and resend.

Attachment is of an unsupported type RIFF (little-endian) data, WAVE audio, GSM 6.10, mono 8000 Hz

Cause
The attached file type (audio file) is not supported.

Solution
Convert the file to a supported format and resend.

Attachment is of an unsupported type Zip archive data, at least v1.0 to extract

Cause
The attached file type (.zip) is not supported.

Solution
Convert the .zip to a supported format and resend.

Email has no access code

Cause
Access code was not entered in the SUBJECT line of the email.

Solution
Resend with a valid access code in the SUBJECT line.

ext: This field is required

Cause
The virtual fax machine’s extension number is not valid or is a reserved number (i.e. 0000).

Solution
Change the virtual fax machine’s extension number and resend.

Not a valid phone number

Cause
The fax number:

  • Was entered incorrectly.
  • Is not a fax number.
  • Is an international number.

Solution
Resend to a valid fax number.

Note: International faxing is not supported (except for in Canada).


Cause
The fax number was entered using dashes (i.e. 801-123-4567).

Solution
Resend without using dashes in the fax number (i.e. 8011234567).

object of type 'NoneType' has no len()

Cause
There is no extension assigned to the virtual fax in the system.

Solution
Set up the virtual fax machine’s extension number and resend.

PBX domain does not exist

Cause
The domain used in the TO field of the email is incorrect.

Solution
Resend using a valid domain.

Process exceeded time limit of 900

Cause
The attached file size is too large.

Solution
Compress the file or separate the file into smaller sections and resend.

Note: A file size smaller than 5 MB is recommended, as larger file sizes have a greater chance for failure.

The call dropped prematurely

Cause
Fax was sent to a number that is not routed to a fax machine or virtual fax machine.

Solution
Route the fax number directly to a virtual fax machine or physical machine or through the detect fax node in a dial plan.

Timed out waiting for initial communication

Cause
The fax number is not directed to a virtual fax machine or physical machine.

Solution
Resend to a valid fax number.

Use outbound DID is false, but no DID is specified

Cause
The virtual fax machine’s External Caller ID was left undefined.

Solution
Enter an External Caller ID for the fax number.

You do not have permission to fax to [fax number]

Cause
The fax number used does not exist.

Solution
Verify the fax number and resend.

Originate Failed - No ANS received

Cause
The fax was sent to an invalid number, the fax machine on the other end did not answer, or there is no fax machine on the other end.

Solution
Verify the fax number and resend.

Could not receive at size of image

Cause
The email format (HTML) is not supported.

Solution
Convert the email message to plain text and resend.

Was this help page useful? Send feedback.

Was this help page useful?


This form is to provide feedback on our help pages. if you need assistance, let's talk—we'd love to hear from you.