Some teachers getting e-mail alerts, others not

Hi there, we are on Moodle 2.2.  We recently cleared up a general e-mail problem that was preventing all messages from getting sent.  We are now getting e-mail from forum postings, and some teachers are getting e-mail alerts from submitted file upload assignments - but not all.  I know of one user in particular who is definitely getting assignment email alerts, and another who is definitely not getting email alerts - and one user who is getting them from one course, but not from another course.  I've checked that the assignments are set to "Yes" for mailing alerts.  Any suggestions as to what else we can try?

Thank you,

Eric Noah

Waunakee Middle School