Although it is often difficult to narrow down exactly why a fax fails, our goal is to provide you with as much information as is available to determine why your fax did not go through. Here is a list of our error reason codes:
- 1000 = fax pending
 - 4000 = fax failed
 - 5000 = fax resource issue
 - 5100 = fax request blocked
 - 5200 = fax document render issue – permanent fail
 - 6000 = fax connect failed
 - 6100 = fax number busy
 - 6200 = fax machine not answering
 - 6300 = fax detection failed
 - 6400 = fax pickup failed
 - 6500 = fax detection failed
 - 6600 = fax detection timeout
 - 6800 = fax negotiation failed
 - 7000 = fax training failed
 - 8000 = fax transmit failed
 - 9000 = fax failed
 
Most often the errors reside in the 6000 block, usually as a result of being unable to connect successfully with the remote fax machine or service.
This can be because of a busy or unavailable line, poor line quality, a bad
connection, an old fax machine, etc.


