We recommend that you set up a rule in Microsoft Outlook to automatically delete messages with [BULK] in the subject line. Use the links below to find Microsoft's directions on setting up email rules depending on the software and version that you use:
 

Messages with a high probability of certainty of being spam are automatically deleted on the spam filter. If the confidence is lower, the spam filter acknowledges the subject status of the message by placing a [BULK] tag in the subject line.