Email notification help

[db]

I have mantis set to notify reporters when any bug is updated in any way. Nobody is recieving notifications. I get them since I'm the administrator, but nobody else is. I used the web interface to set up the email notifications. All relevant boxes are ticked. More or less all the boxes are ticked down all the columns but the administrator and viewer access level columns. What could be the problem? I haven't changed any email notification settings in config_inc.php btw.