Accept incoming emails from employees and contacts existing in the account only
When this setting is activated, you prevent the creation of new tasks and contacts by email if the email is sent from an address not in the system. This is a fairly severe restriction: among other things, it prevents you from receiving emails from your contacts' alternate email addresses before they have been deliberately added to the system. On the other hand, it's a very efficient way to protect against spam.
Because of this, we recommend this setting for people who aren't using Planfix with external contacts. Activating it essentially makes it impossible for unsolicited information to reach you. For accounts that regularly work with external contacts by email, we recommend other methods of spam protection: