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Deploy and configure Microsoft Office 365 with Area 1 as MX Record

A schematic showing where Area 1 security is in the life cycle of an email received

In this tutorial, you will learn how to configure Microsoft Office 365 with Area 1 as MX record. This tutorial is broken down into several steps.

​​ 1. Add Area 1 IP addresses to Allow List

  1. Go to the Microsoft Security admin center.

  2. In the Threat management section, select Policy settings.

    Select threat management

  3. Select the Anti-spam option.

    Select the anti-spam option

  4. Select Connection filter policy (Default) to edit the policy, and then select Edit connection filter policy.

    Select edit connection filter policy

  5. In Always allow messages from the following IP addresses or address range add the IP addresses and CIDR blocks mentioned in Egress IPs.

    Enter the egress IP addresses

  6. Select Save.

​​ 2: Execute Enable-OrganizationCustomization (if required)

The following steps are only required if you have not previously customized your Office 365 instance. If you received the message to run this cmdlet in the previous step, you will need to execute it in order to proceed with the configuration.

  1. Run PowerShell as administrator, and execute the following command. Reply Yes when prompted:
PS C:\Windows\system32> Install-Module ExchangeOnlineManagement

Run the install-module command in PowerShell

  1. Run the following commands to execute the policy change and connect to the Office 365 instance:

    PS C:\Windows\system32> set-executionpolicy remotesigned

    Confirm that you want to execute the policy change, and then run the following command:

    PS C:\Windows\system32> Import-Module ExchangeOnlineManagement

    Finally, run the following to authenticate against your Office 365 instance:

    PS C:\Windows\system32> Connect-ExchangeOnline

    Run the commands to execute the policy change

  2. The Connect-ExchangeOnline cmdlet will prompt you to login. Log in using an Office 365 administrator account. Once authenticated, you will be returned to the PowerShell prompt.

    Log in with an Office 365 admin account

  3. You can verify that the OrganizationCustomization is enabled by running the command:

PS C:\Windows\system32> Get-OrganizationConfig | FL isDehydrated

Run the get-organizationconfig command

If the result is false, OrganizationCustomization is already enabled and no further actions are required. If it is true, you need to enable it:

PS C:\> Enable-OrganizationCustomization

If the previous result is true, enable the organization customization mode

​​ 3. Enhanced Filtering configuration

This option will allow Office 365 to properly identify the original connecting IP before the message was received by Area 1. This helps with SPF analysis. This has two steps:

  • Creating an inbound connector.
  • Enabling the enhanced filtering configuration of the connector.

​​ Create an inbound connector

  1. From the Microsoft Exchange admin center, select mail flow > connectors.

    Select connectors from mail flow

  2. Select the + icon to configure a new connector. In the Select your mail flow scenario panel dialog box that opens:

    1. In the From dropdown: select Partner organization.
    2. In the To dropdown: select Office 365.
    3. Select Next to continue the configuration.

    Configure your mail flow

  3. Provide a Name and a Description for the new connector. Leave the Turn it on checkbox enabled. Select Next.

    Provide name and description for the new connector

  4. Select Use the sender’s IP address in the How do you want to identify the partner organization? configuration panel. Select Next.

    Select the sender’s IP address

  5. In What sender IP addresses do you want to use to identify your partner? add the IP addresses and CIDR blocks found in Egress IPs. Select Next.

    Enter Area 1’s egress IP addresses

  6. Keep the Reject email messages if they aren’t sent over TLS checkbox enabled. Select Next.

    Keep the Reject email messages if they aren’t sent over TLS checkbox enabled

  7. Review the connector configuration and select Save.

    Review settings

​​ Enable enhanced filtering

Now that the inbound connector has been configured, you will need to enable the enhanced filtering configuration of the connector. Exit the Exchange Admin console, return to the main Office 365 Administration Console and select the Security admin console.

The security admin console

  1. Go to Security Admin console > Threat Management > Policy, and select Enhanced filtering.

    Go to Enhanced filtering

  2. In Enhanced Filtering for Connectors, you will find the connector that was previously configured. Double click the connector to edit its configuration parameters.

  3. Select Automatically detect and skip the last IP address and Apply to entire organization.

    Select Automatically detect and skip the last IP address, and Apply to entire organization

  4. Select Save.

​​ 4. Configure Area 1 Quarantine Policies

​​ Select the disposition that you want to quarantine

Quarantining messages is a per domain configuration. To modify which domains will have their message quarantines, access the domain configuration:

  1. Log in to the Area 1 dashboard.

  2. Go to Settings (the gear icon) > Domains.

  3. Locate the domain you want to edit.

  4. Select the ... icon > Edit.

  5. Select the additional dispositions you want to quarantine.

    Manage domain quarantines

​​ Manage the Admin Quarantine

  1. Log in to the Area 1 dashboard.

  2. Go to Email > Admin Quarantine.

  3. Locate the message you want to manage, and select the ... icon next to it. Thill will let you preview, download, or release the quarantined message.

    Manage admin quarantines

​​ Optional - Quarantine messages using Microsoft Hosted Quarantine

As previously noted, malicious and spam detections are automatically quarantined in Area 1’s quarantine (this behavior cannot be modified). However, for the suspicious and spoof dispositions, you may prefer to apply a different behavior, where these messages can be quarantined into the Microsoft Hosted Quarantine or sent to the user’s junk folder.

For this alternate behavior, you will need to configure a transport rule in Office 365:

  1. Go to the Exchange administrator console > mail flow > rules.

    Select rules from the Exchange admin console

  2. Select the + button > Create a new rule.

    Create rule

  3. In the new dialog box, select More options to open the advanced version of the rule creator. Set the following conditions and actions:

  • Name: Quarantine Area 1 Suspicious Messages
  • Configure the first condition, select A message header > Includes any of these words:
    • Enter text: X-Area1Security-Disposition
    • Enter words: SUSPICIOUS
  1. Select the add condition button to add a second condition.

  2. In the new condition, select The sender > IP address is in any of these ranges or exactly matches and enter the egress IPs in the Egress IPs page.

  3. In the Do the following section, select Redirect the message to > hosted quarantine..

    Redirect messages to hosted quarantine

  1. Select Save to save the new rule.

​​ 5. Update your domain MX records

Instructions to update your MX records will depend on the DNS provider you are using. You will need to update and replace your existing MX record with the Area 1 hosts:

MX PriorityHost

When configuring the Area 1 MX records, it is important to configure both hosts with the same MX priority. This will allow mail flows to load balance between the hosts.

Once the MX records have been updated, the DNS updates may take up to 36 hours to fully propagate around the Internet. Some of the faster DNS providers will start to update records within minutes. DNS changes will reach the major DNS servers in about an hour.