To prevent sender forgery, you can specify a sender domain within the message header address and the allowed IP addresses for the domain.
Trend Micro Email Security provides a built-in default rule that has the lowest priority to ensure you receive a baseline level of protection. The default rule cannot be deleted.
You can create only one single rule for each "Managed Domain". The default rule will be applied if no other rules are matched based on the "Managed Domain".
The Add Sender IP Match Settings screen appears.
example.com
subdomain.example.com
*.example.com
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