This Article describes a situation where you have whitelisted an external sender's domain, but emails are still blocked by Antispam Service.
Email Security.cloud
The whitelisted domain has been added with a wildcard (*) example : *domain.com or using (@) example: @domain.com this method invalidates a proper bypass for the Antispam Service.
In order to properly bypass the Antispam service, Administrators are advised to add the external sender's domain without any additional wildcard (*) or (@) sign. Example : Domain.com
Note: The whitelist or approving a sender Email / domain / IP works ONLY for the external senders ( inbound traffic ). If you encounter any outbound Issues we recommend that you Contact Support.