There could be several reasons why the needle threader cannot be used.
Check the following points or issues.

• The needle is not at the correct position.
  Touch the key to move the desired needle bar to be threaded into embroidering position.


• Recommended needles are not used on this machine.
  Replace and use recommended needle.


• The needle is not installed correctly.
  Correctly install the needle.
   
• The hook on the automatic threading mechanism is bent.
  Consult your nearest authorized Brother dealer.