Follow the below steps to learn how to bypass this Mimecast Policy:
Log in to your Mimecast administration console.
Select Administration, then select Gateway, then Policies.
Scroll down and select Impersonation Protection Bypass.
Either select the:
Policy to be changed.
New Policy button to create a policy.
Emails From
In the Addresses Based On field, select The Return Address (Email Envelope From).
In the Applies From field, select External Addresses.
Emails To
In the Applies To field, select Internal Addresses.
Validity
In the Enable/Disable field, select Enable.
In the Set Policy as Perpetual field, ensure the policy is set to Always On.
In the Policy Override field, check the box.
This overrides the default order that policies are applied. If there are multiple applicable policies, this policy is applied first unless more specific policies of the same type are configured with an override.
In the Source IP Ranges, input Nectar's delivery server IP address:
159.183.82.50
Select Save and Exit
Congrats! You've configured Mimecast to allow emails sent by Nectar to bypass external tagging!