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      How can I fix issues with messages not sending when Outlook is connected?

      What Should I Do if My Messages Fail to Send with Outlook Connected? Why aren’t my messages sending through Outlook, and how can I resolve it?

      If you're using an Outlook email account with your Investor Matching account and messages fail to send, the issue is most likely due to your SMTP settings being disabled. You may see this error message:

      Invalid login: 535 5.7.139 Authentication unsuccessful, SmtpClientAuthentication is disabled for the Tenant.

      How to Fix It

      1. Enable SMTP AUTH in Outlook

        • The error occurs because Outlook has SMTP AUTH disabled by default for some tenants.

        • You (or your Microsoft admin) need to turn it back on.

      2. Follow Microsoft’s Instructions

        • Microsoft provides a step-by-step guide here:
          👉 Enable SMTP AUTH in Outlook (Microsoft Help Article)

        • Enable SMTP AUTH for specific mailboxes
          The per-mailbox setting to enable (or disable) SMTP AUTH is available in the Microsoft 365 admin center or Exchange Online PowerShell.

          Use the Microsoft 365 admin center:

          • Open the Microsoft 365 admin center and go to:
            Users > Active users

          • Select the user, and in the flyout that appears, select Mail

          • In the Email apps section, select Manage email apps

          • Verify the Authenticated SMTP setting:

            • Unchecked = disabled

            • Checked = enabled

          • When you're finished, select Save changes

      3. Test the Connection in Investor Matching

        • Return to Investor Matching.

        • Go to Email & Settings > Email Account Setup

        • Click the Test Delivery button to verify if the issue is resolved.

        • If successful, your email connection will now send messages without any errors.

      Notes

      • This is a Microsoft-side setting that applies specifically to Office 365/Outlook accounts.

      • If you’re part of an organization, you may need your IT administrator to make the change for you.

      • Once SMTP AUTH is enabled, messages should send normally from your connected Outlook account.