The Comm. Error message may appear on the Brother machine's LCD if the machine experienced a communication error while sending or receiving a fax. This type of error is generally caused by interference on the telephone line, an incorrect telephone line connection, or an alarm system or other device on the line.

1. Press the Hook key and verify the quality of the dial tone.
   
   
   • If the dial tone quality is poor, contact your local telephone company for further assistance.
     
     
   • If the dial tone is clear, go to Step 2.
   
   
   
2. Check the telephone line connection.
   

   If the telephone line is plugged into any device other than the wall telephone jack (surge protector, switching device, etc.), disconnect the line from that device and plug it directly into the wall telephone jack. This is for testing purposes. Removing such devices helps to determine whether the issue is related to the Brother machine or another device.

   
   
3. Once the telephone line is plugged directly from the jack labeled Line on the Brother machine to the wall telephone jack, try to re-send the fax.
   
   
   • If the fax is successful, the problem was caused by another device or piece of equipment on the line.
     
     
   • If your Brother machine displays the Comm. Error again, go to Step 4.
   
   
4. Your Brother machine has a Compatibility setting that adjusts its sensitivity to interference on the telephone line by lowering the transmission speed.
   

   Change your Brother machine's Compatibility setting by following these steps:

   
   
   1. Press Menu, 2 (Fax), 0 (Miscellaneous), 1 (Compatibility).
      
      
   2. Press the UP OR DOWN ARROW key to select Basic (for VoIP).
      
      
   3. Press the OK key.
      
      
   4. Press the Stop/Exit key.
   
   

   When you change the Compatibility to Basic (for VoIP), the Error Correction Mode (ECM) feature is not available.

   
   
5. Try to send another fax.
   
   
   • If the fax goes through with no error message, then you were able to compensate for the telephone line.
     
     
   • If the Comm. Error message continues to appear, do the following:
     

     Contact your telephone provider and have them test the line.

     Connect your Brother machine to a different, known-working telephone line and test the sending and receiving functions.

     
     

     If the "Comm. Error" message continues to appear after you have the line checked and test the Brother machine on a different, known-working telephone, please contact Brother Customer Service from "Contact Us".