Troubleshooting Guide: Setting Up SMTP Providers

Overview

Configuring an SMTP provider ensures your emails are delivered securely and reliably. Issues often occur due to authentication errors, DNS misconfigurations, or provider restrictions. This guide explains how to set up common SMTP providers (Gmail, Office 365, Amazon SES) and troubleshoot the most frequent problems.

Q1: How do I set up a Google/Gmail account as my SMTP provider?

A1:
Steps to Set Up:

• Go to Settings → Email Services → Add New Service.

• Select Google/Gmail from the list of providers.

• Follow the on-screen instructions to authenticate and link your Gmail account.

• Send a test email to confirm the SMTP connection is working.

Fix: If issues occur, check that:

• 2-step verification is disabled.

• The correct Gmail SMTP server address and port are entered.

Q2: Why does my SMTP integration show “Authentication Unsuccessful” with Microsoft Office 365, even with 2-step verification off?

A2:
Microsoft requires SMTP Authentication to be enabled for third-party apps.

How to Fix:

• Log into your Office 365 account.

• Go to Security & Privacy and enable SMTP Authentication.

• Verify that the correct SMTP server address and port are entered.

• Test by sending a sample email.

Fix: Once SMTP Authentication is enabled, the integration should work. If issues persist, contact Outlook support.

Q3: My Amazon SES SMTP integration is not sending emails. What should I check?

A3:
Amazon SES requires proper IAM credentials and DNS configuration.

How to Fix:

• Confirm the correct SMTP server address is used.

• Use port 465, as required by SES.

• Verify IAM Username and Password are correct.

• If in sandbox mode, request production access in the SES console.

• Test the connection.

Fix: Double-check credentials and ensure production access is granted. Review SES logs if problems continue.

Q4: Why can’t I use my free email address (like Gmail) as the SMTP provider?

A4:
Free email services (e.g., Gmail, Yahoo) limit SMTP use and may block accounts sending bulk emails.

How to Fix:

• Use a professional email address or dedicated sending domain.

• Confirm your provider supports SMTP relay and check daily limits.

• If using Gmail, set up SPF, DKIM, and DMARC to improve deliverability.

Fix: For reliable, high-volume sending, use a dedicated service like SendGrid or Mailgun.

Q5: My emails haven’t been delivered since setting up SMTP. What could be causing this?

A5:
Possible causes include DNS misconfiguration, incorrect SMTP details, or provider limits.

How to Fix:

• Check DNS Records: Ensure SPF, DKIM, and DMARC are correctly configured.

• Verify SMTP Settings: Confirm server address and port match your provider.

• Check Sending Limits: Ensure you haven’t exceeded daily limits.

• Review Email Content: Avoid spammy keywords and attachments.

Fix: Correct DNS, settings, or limits. If still unresolved, contact your provider’s support.