How to find this setting:
Trend Micro Anti-Spam Toolbar > Trend Micro
> Settings > Approved Senders
Available only in select versions of Trend Micro security software.
Use the Approved Senders list to ensure that messages sent from specific email accounts will not get identified as spam. Remember to click OK after making any changes.
If you edit or remove the email address of an approved sender, messages from that address could potentially be identified as spam. Think carefully before changing or removing any email address.