In response to the university’s request to limit the number of unsolicited email messages (spam) arriving in APU inboxes, IMT has implemented a centralized spam detection system called Symantec Brightmail Anti-Spam (Brightmail).
[Spam] Brightmail works by scanning all incoming email messages before they reach APU inboxes and tagging the message subjects with “[Spam]” if they meet specific criteria defined by the Brightmail filters.
Symantec has email probes set around the Internet for detection of new spam.
Symantec technicians create custom rules to block this spam in realtime.
The email's From address may not match where the email was actually sent from.
Try viewing the email headers and whitelist the sending address shown there. If the original email is quarantined by any recipient, only one copy is stored in that particular Spam folder.
In other words, this filter will catch 95 percent of your spam.