I am trying to send a mass mailing using Maxbulk Mailer. I am on an Office 365 Exchange server. I have seen others having a problem in the forums. I seem to be experiencing the same issues - cannot send messages. If I use ESTMP, I get an error saying the server rejected the message because I haven't authenticated myself and to check the settings (I have the correct email address and password). I've tried the other authentication choices with no success as well. Could someone please provide what the settings need to be as far as authentication and other settings go?