Set up Email Security with Microsoft 365 in Nebula

Email Security in Nebula is vital for protecting organizations from email threats like phishing and malicious activities that can compromise sensitive data and disrupt operations.

This article outlines steps to integrate Email Security with Microsoft 365, helping organizations secure their mailboxes and focus on their core activities without worrying about email attacks.

Before you begin

• Be a Microsoft 365 Global Admin and a Nebula Super Admin.
• Have a list of email domains to protect.
• Have a business email address to receive setup confirmation.

Step 1: Connect your email provider

1. In Nebula, go to Manage > Email Security.
2. Click Set Up Email Security.
3. Select Microsoft 365 as the email provider.
4. Enter the email domains to protect. An email domain is the part that comes after the @ in an email address. More domains can be added later from the Configurations > Domains page.
5. Select the region to store and process email data based on your compliance requirements. The data center options are the United States (Oregon) or European Union (Germany).
6. Provide an email address to receive a confirmation once mailbox syncing is complete. Mailbox syncing happens at the end of this setup and can take up to 24 hours. This email address must belong to one of the domains entered above.
7. Click Authorize and Enable API.
8. A Microsoft 365 login window opens. Sign in with your Microsoft 365 Global Admin credentials and click Accept.
9. Return to the Nebula tab to continue.

Note: If you made a typo and are receiving error messages when trying to set up the correct email domain, contact Support.

Step 2: Choose a protection mode

Choose how Email Security should handle email threats and click Next.

Change this setting later on the Configurations > Protection Mode page.

Step 3: Select mailbox groups to protect

In Microsoft 365, organize each mailbox into mailbox groups to make bulk management easier. Choose which mailbox groups to sync with Nebula and click Next. Any changes made to the selected mailbox groups in Microsoft 365 are automatically reflected in Nebula. 

For example, when an employee is offboarded, they should be removed from the mailbox group in Microsoft 365. This automatically removes the mailbox from Email Security in Nebula as well.

• All mailboxes in domain(s) – Protects all mailboxes under the selected domains. If your mailboxes are not organized into mailbox groups or you're unfamiliar with how the mailbox groups are configured, select all mailboxes and disable individual mailboxes from the Configurations > Mailboxes page.
• Mailbox groups – Choose specific mailbox groups to protect.
  • Check Include shared mailboxes to protect those as well.

The mailbox group selections can be changed later from the Configurations > Mailboxes page. 

Step 4: Review and complete setup

1. Review the:
   • Email domains
   • Protection mode
   • Selected mailbox groups
2. Click Complete Setup.

Mailbox syncing starts immediately and may take up to 24 hours. A confirmation email is sent to the email address entered in step 1 once the sync is complete.

Nebula also runs a one-time informational scan of the last 90 days of emails in Microsoft 365 to identify any past threats. The recipients can manually delete any malicious emails reported by this scan to remediate these threats.

Next steps

To enhance your protection, we recommend the following: 

• Set Up a Report Phishing Mailbox - Allow users to report suspicious emails. These reported emails appear in the Email Incidents > Needs Attention tab for admin review. See Set up Report Phishing with Email Security.
• Enable Email Security Notifications - Notify admins when users report phishing emails or request quarantined emails to be released back to their mailbox. See Set up Email Security notifications.

Return to Email Security guide.