Adding PTR Domains

  1. Go to Inbound Protection > Connection Filtering > Reverse DNS Validation.
  2. Click the Blocked PTR Domains tab and click Add.
  3. On the Add Blocked PTR Domain screen, configure information about the PTR domain from which you want to block messages.
    1. Specify a domain name in one of the following formats:


      • *

        This format matches all the subdomains under the domain, for example,,

    2. Type a description for the domain.
    3. In the Exception(s) section, specify exceptions to the blocked PTR domain and click Add.

      The domains in the exception list must be subdomains of the blocked PTR domain. Trend Micro Email Security does not block messages from these subdomains.

      To delete an exception, select the exception item and click Delete.

    4. Click Save.

      The blocked PTR domain appears in the blocked PTR domain list.

To remove a blocked PTR domain, select a PTR domain and click Delete. You can also select the checkbox in the table heading row to select all rules.