6450 Request Error. Fannie Mae DO/DU exception has thrown


The Request error Fannie Mae DO/DU exception has thrown occurs when submitting a file to Fannie Mae.



  • Invalid Casefile ID
  • Invalid login attempt



Clear the Casefile ID field

  1. Open the Point file.
  2. Select Interfaces > Fannie Mae > Results.
  3. Click Edit.
  4. Remove the content in the Casefile ID field.
  5. Click Ok.
  6. Resubmit the loan to Fannie Mae.


Verify Fannie Mae log in information and delete the Fannie.ini file.

Verify that you can log in to the Fannie Mae website.

  1. Go to www.efanniemae.com.
  2. Click Launch DO or Launch DU.
  3. Enter your user ID and password.
  4. If you are not able to log in to the Fannie Mae website, contact Fannie Mae to resolve the login error.

Delete the Fannie.ini file

6011 Removing the fannie.ini file