Trend Micro Email Security allows you to import approved and blocked senders in batches from a properly-formatted CSV file.
To import senders and recipients in pairs, click Import on the tab.
To import senders for a specific recipient, click a recipient name, and click Import in the dialog box that appears.
Merge: append the sender email addresses or domains to the existing list.
Overwrite: replace the existing list with the sender email addresses or domains in the file.
You can click Download sample file to view a sample of a properly formatted file.
Trend Micro Email Security checks all the entries in the selected file to identify any invalid, duplicate, conflict, excessive email addresses or email addresses from unmanaged domains.