Know how many firewall rules can be set in WFBS.
The maximum number of firewall rules that can be set in WFBS depends on the number of exceptions configured in one policy or rule. The maximum number of limitations that can be inserted in a policy or rule is 1024. Also, the number of exception rules configured in one policy may affect how many rules can get inserted.
For example, you configure an exception rule to apply to both Inbound and Outbound direction, and then the Trend Micro Common Firewall Module or Network Security Component Module (NSC) will create 2 separate firewall rules for it. This means that if there are already 512 exception rules (512 x 2 = 1024), then the 513th exception rule is over the maximum number and will be discarded by the NSC module.
For more information on NSC, refer to this Microsoft article: Network Security Components.