Great question! If you're asking this kind of question, then you are thinking correctly about your email security and delivery.
Simply put, many companies have additional tools that monitor user inboxes for domains that appear suspicious or 'phishy.' Since Hook Security updates its domains used for testing and training each month, we ask that organizations add the new 1-3 domains to their internal "Safe List" (Microsoft Office) or "Whitelisted domains" (G Suite).
In doing so, Hook Security testing simulations and training pages are more likely to arrive in the user email inbox. This allows for more thorough and accurate testing and training experiences.
Notice: Please update your Microsoft Connector to avoid 451.xxx errors.
Note: It is a best practice to remove the old whitelisted domains after the completion of the training experience each month. Do not accumulate whitelisted domains.