Email notifications don't work

I’m only getting job complete notifications for two users out of about 15.
Every user has the correct email address and “send email notifications” enabled in “manage users” dialog.
15 users are sending 3dsmax jobs and only 2 are getting notification on complete/failure/etc.

What to do?

What’s usually unexpected is that the Slaves and Monitors are what send those e-mails. Essentially, wherever the state was changed is where the e-mail comes from.

The big question is does your e-mail server have filtering in place? That was the problem here: