Exchange 2010 SMTP protocol error. 504 5.7.4 Unrecognized authentication type
Last Updated: 8/22/15With GFI fax maker running on my Exchange 2010 server I was getting this error when trying to use the, restore to mailbox feature:
error:
SMTP protocol error. 504 5.7.4 Unrecognized authentication type
solution:
on the hub transport receive connector I could have just unchecked the box "offer basic authentication only after starting TLS", but I didn't want to degrade my security by sending usernames and passwords over non-secured connections.
So, I created a new received connector on the server and duplicated the settings of the original connector. Except I only included the local host IP address (127.0.0.1) and the primary server IP address and I unchecked the box mentioned above. it seems to have worked.