Connect Mission Inbox Senders

Purpose

Mission Inbox is SuperSend's managed email infrastructure. This article covers how to connect Mission Inbox to SuperSend so you can create senders from Mission Inbox-provisioned mailboxes. There are two Mission Inbox connection types: SMTP (for standard mailboxes) and OBM API (for high-volume sending).

Prerequisites

• A Mission Inbox account with at least one active mailbox or sending domain.
• Your Mission Inbox API key (found in your Mission Inbox account settings).
• You must first connect Mission Inbox at the integration level if you want to bulk-import mailboxes or use OBM API senders.

Step 1: Connect the Mission Inbox Integration

If you haven't already connected Mission Inbox as an organization-level integration:

1. Go to Admin → Integrations tab.
2. Select your team from the dropdown.
3. In the Sending Providers section, find MissionInbox.
4. Click Manage → Add Account.
5. Enter your Mission Inbox API Key.
6. Click Save.

SuperSend will sync your Mission Inbox domains and mailboxes. This may take a moment.

If you only need to connect individual mailboxes via SMTP/IMAP manually, you can skip this step.

Step 2: Add Mission Inbox Mailboxes as Senders

There are two ways to add Mission Inbox mailboxes:

Option A: Manual SMTP Connection (Single Mailbox)

Use this when you have SMTP/IMAP credentials for a specific Mission Inbox mailbox and want to connect it directly.

1. Go to Senders → Add Sender → Email Sender.
2. Click Connect Your Own Mailboxes.
3. On the provider list, click Mission Inbox SMTP.
4. Enter the SMTP/IMAP credentials from your Mission Inbox dashboard:

• SMTP Host, SMTP Port, SMTP Secure
• IMAP Host, IMAP Port, IMAP Secure
• IMAP Username (your mailbox email address)
• IMAP Password

5. Click Connect.

The mailbox appears in Senders → Mailboxes once connected.

Option B: OBM API Sender (High-Volume)

Mission Inbox OBM API senders are for high-volume sending through Mission Inbox's outbound mail infrastructure. Unlike SMTP senders, OBM API senders don't use IMAP and don't support reply detection (replies must be handled via separate inbox or routing configuration).

1. Go to Senders → Add Sender → Email Sender.
2. Click Connect Your Own Mailboxes.
3. On the provider list, find and click Mission Inbox OBM API under "Email API Providers."
4. Enter:

• API Key — your Mission Inbox API key.
• Send As Email — the email address you're sending from.
• Reply-To Email — where replies should be directed (can be a different address).
• Track Replies — toggle based on whether your Mission Inbox plan supports reply detection.

5. Click Connect.

Step 3: Attach to a Sender Profile

After adding Mission Inbox mailboxes, they need to be attached to a sender profile before they can be used in campaigns:

1. Go to Senders → Sender Profiles tab.
2. Open a sender profile (or create one).
3. Click Add Mailboxes and select the Mission Inbox mailboxes you just connected.
4. Save.

See Create and Use Sender Profiles for the full details.

Expected Result

Mission Inbox mailboxes are connected as senders in SuperSend and visible in the Mailboxes tab, ready to be added to sender profiles.

Troubleshooting

• Issue: Mission Inbox integration saved but mailboxes don't appear for bulk import.

Fix: Verify the API key is correct. Allow a minute for sync to complete, then refresh the Senders page. Check that your Mission Inbox account has active mailboxes provisioned.

• Issue: SMTP connection fails for a Mission Inbox mailbox.

Fix: Copy the SMTP/IMAP credentials directly from your Mission Inbox account dashboard — don't guess port numbers. Confirm the mailbox is active and not suspended in Mission Inbox.

• Issue: OBM API sender connected but emails aren't going out.

Fix: Verify the sending domain is verified and active in your Mission Inbox account. Also confirm the sender profile is assigned to the campaign.

Related Articles

• Mission Inbox Integration Setup
• Connect SMTP/Bulk Provider Sender
• Create and Use Sender Profiles

Updated on: 17/03/2026