My preferences
My preferences are just for you: where your emails go, and which ones you get.
Your email address
Your emails go to your address in Active Directory. To use another, enter it under Email address; leave it empty to use the one from Active Directory. Without either, you won't get emails.
Which emails you get
Each email you could get is listed. Untick any you don't want, and choose Save. What each one is, and who it goes to, is on Email.