Anti-Spoofing in Mimecast

This article will guide you or your technical team through bypassing this Mimecast policy.

• Log in to your Mimecast administration console

• Select Administration, then select Gateway, then Policies
• Scroll down and select Anti-Spoofing

Options

• Click New Policy
• In the Policy Narrative field, type Workshop IP Permit (Or whatever else will help track this policy.)
• In the Select Option field, select Take No Action

Emails From

• In the Addresses Based On field, select Both
• In the Applies From field, select Everyone
• In the Specifically field, select Applies to all Senders

Emails To

• In the Applies To field, select Everyone
• In the Specifically field, select Applies to all Recipients

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, enter the IPs that correspond with your Workshop server
  1. 1. US SERVER 

        1. 149.72.151.35/32
           149.72.183.8/32
           149.72.201.153/32
           149.72.22.42/32
           149.72.61.106/32
           159.183.141.212/32
           159.183.141.213/32
           159.183.141.214/32

     2. EU SERVER

        1. 159.183.224.19/32
           159.183.227.196/32
           159.183.229.133/32
           159.183.229.134/32

• Select Save and Exit

Congrats! You've configured Mimecast to allow emails sent using Workshop to bypass Anti-Spoofing!