Note: Bulk uploading Outlook accounts is currently unavailable because Outlook requires authentication via OAuth for each connection.
Connecting your Outlook account to Smartlead is done via OAuth - a secure login flow that doesn't require you to share your password with Smartlead directly.
You'll need to enable Authenticated SMTP and IMAP for your Outlook account in Microsoft 365 before connecting to Smartlead.
Here's how:
Log in to your Microsoft 365 Admin Center at admin.microsoft.com
Go to Users → Active Users
Click on the user account you want to connect
In the flyout panel that appears, click the Mail tab
Under Email Apps, click Manage Email Apps
Check the boxes for Authenticated SMTP and IMAP
Click Save Changes
Wait 20–30 minutes before proceeding. Changes can take time to reflect.
For more details, refer to Microsoft's official guide: Enable SMTP Authentication in Microsoft 365
Once done, wait 20–30 minutes before proceeding to the next steps.
Go to Email Accounts from the left-hand sidebar on your Smartlead dashboard.
Click + Connect Mailbox in the top-right corner. A setup modal will open.
Choose your infrastructure type as Smartlead's Infrastructure.
Select Outlook as your provider.
Enter your Outlook email address and password when prompted, then click Sign In.
A permissions prompt will appear requesting access for the Smartlead app — click Accept.
Once verified, your mailbox shows a green Connected status and is ready to use in campaigns.
Outlook requires OAuth authentication for each connection individually. Bulk CSV upload is not supported for Outlook accounts at this time.
Try disconnecting and reconnecting. Make sure you click Allow or Accept on every permission screen during the OAuth flow. If the issue persists, verify that Authenticated SMTP and IMAP are enabled in your Microsoft 365 Admin Center and that 20–30 minutes have passed since enabling them.
You need Microsoft 365 admin access to enable Authenticated SMTP and IMAP - this is a one-time setup step. Once enabled, individual users can connect their own accounts to Smartlead without admin access.
