In the last several weeks, I have been sending faxes form the HP Officejet Pro 8500 a909g and noticed that some of my faxes were not being sent. The call would drop during the middle of the transmission of the first fax page.
After updating the firmware from DLM1FN0842BR to DLM1FN0924AR which did not solve the problem and reading through some user comment's to slow down the fax transmission, I finally read the FAQ on the H-P site for this error code and pulled out my old very long trustworthy phone cord which was about 20 years old and replaced it with two new cords with a connector between them. I re-sent the fax and it worked! This is embarrassing since I was once in the fax business and should have got on my knees and checked the cord length as step 1. In any regard, it's now fixed!
Error Code: 396, 397, 398, 399, 400, 401, 402, 403, 405, 406, 407, 408, 409, 410, 411, 412, 413, 414, 415, 416, 417, 418, 419
During a V.34 transmission, the local machine is unable to connect (handshake) with the remote machine and is consequently unable to send a T30 frame. This occurs when the line is disconnected or if line conditions degrade during the session.
Remove any pass-through devices from the phone line, and then try the fax again.
Confirm that the fax/phone cable is no longer than required, and that it does not pass near unshielded electric motors such as fans, heaters, or household appliances.
Try to send the fax at a different time when telephone line conditions have improved.