Articles on: Senders

Connect Outlook / Microsoft Sender

Connect Outlook / Microsoft Sender


Purpose


Microsoft Outlook and Office 365 mailboxes can be connected to SuperSend using OAuth or manual configuration. This article covers both paths so you can get a Microsoft mailbox sending as quickly as possible.


Before You Start


Read Senders Overview if this is your first time setting up senders. Connecting a mailbox is step one — you'll still need to attach it to a sender profile and assign that profile to a campaign before any email goes out.


Open the Connection Wizard


  1. Go to Senders in the left sidebar.
  2. Click Add Sender → Email Sender.
  3. On the method selection screen, click Connect Your Own Mailboxes.
  4. On the provider list, click Microsoft Outlook.



OAuth connects your Outlook mailbox through Microsoft's authorization flow without storing your password in SuperSend.


Steps:


  1. Select the OAuth tab (default).
  2. If your team already has a Microsoft OAuth app configured, it appears here. Click to select it.
  3. Click Connect Your Microsoft Account.
  4. A Microsoft sign-in window opens. Sign in with the account you want to connect.
  5. Review the permissions requested and click Accept.
  6. You're redirected back to SuperSend. The mailbox appears in your sender list.


If no OAuth apps appear: Your team admin needs to create one first. Click Create OAuth App and enter your Azure App Registration credentials (Application ID, Client Secret, Tenant ID, and Redirect URI). Once saved, it will be available for all team members to use when connecting their Outlook accounts.


Method 2: SMTP/IMAP (Manual)


For accounts where OAuth isn't available, or for hosted Exchange accounts that aren't on Microsoft's standard OAuth flow, you can connect using SMTP and IMAP credentials directly.


Steps:


  1. Click the SMTP/IMAP or Manual tab.
  2. Enter:
  • Email — your full Outlook or Office 365 email address.
  • Password — your account password (or an app password if your admin requires it).
  • Send As Name — the display name recipients see.
  • SMTP and IMAP settings are pre-filled with Microsoft's standard settings. If your organization uses custom Exchange settings, update them here.
  1. Click Connect.


Note on App Passwords: If your Microsoft 365 tenant has multi-factor authentication enforced, regular passwords won't work for SMTP/IMAP. You'll need to generate a Microsoft App Password from your Microsoft account security settings.


After Connecting


The mailbox appears in Senders → Mailboxes with its email address and connection status. Attach it to a sender profile:


  1. Go to Senders → Sender Profiles tab.
  2. Open a profile (or create one).
  3. Click Add Mailboxes and select this mailbox.


See Create and Use Sender Profiles for full details.


Expected Result


The Outlook mailbox shows as active in Senders → Mailboxes and is available to add to sender profiles.


Troubleshooting


  • Issue: OAuth connection shows "Need admin approval" from Microsoft.

Fix: Your organization's Azure AD admin has restricted OAuth app consent. The admin needs to grant consent for the SuperSend app registration in Azure, or switch to the SMTP/IMAP method.


  • Issue: SMTP/IMAP connection fails with "authentication failed."

Fix: If your account has MFA enabled, standard passwords are blocked for SMTP. Generate and use an App Password from your Microsoft account security settings.


  • Issue: Mailbox connects but doesn't receive incoming replies.

Fix: Confirm that IMAP is enabled on the account. In Outlook web settings, go to Mail → Sync email → toggle IMAP on.



Updated on: 17/03/2026

Was this article helpful?

Share your feedback

Cancel

Thank you!