Troubleshooting Email Sending Delay

This guide will help you identify and resolve common issues that can cause delays in emails sent through Descope. Whether you’re a developer or an IT administrator, these steps will assist you in troubleshooting and resolving email delivery delays.

Testing Options

Before diving into detailed troubleshooting, ensure that your email configuration settings in Descope and your email server are correct. This includes verifying the sender email address, SMTP server settings, etc.

Check Email Gateways

Does your customer use an email gateway, such as Cisco IronPort Secure Email Gateway? Email gateways can sometimes introduce delays due to security checks, filtering, or rate limiting. Ensure the email gateway settings are optimized for timely email delivery.

Gathering Logs

Descope provides detailed logs that can be accessed through the Audit tab. Look for the following logs to diagnose email sending issues:

Analyzing the .eml File

If you can obtain the .eml file of the delayed email, it would be very helpful for a detailed analysis. Here is a guide on how to export an email to a .eml file: Export Email to File. Once you have the .eml file, you can use tools like EML Analyzer to examine the headers for any indications of delays. Here's an example of how to analyze the timeline of an email:

Example Analysis

1. Email Created: 14:20:15 on AWS
2. Received from AWS by example.com (Secure Email Gateway): 14:20:17 (+2 seconds)
3. Received from example.com by destination.com (Webmail): 14:25:22 (+5 minutes)

The email was flagged by the Secure Email Gateway as potential spam, likely causing it to be held for further scanning. The Secure Email Gateway headers are encrypted, so the exact cause of the delay needs to be confirmed with the customer's Secure Email Gateway details.

Evidence from EML

Received: from mx1.example.com ([203.0.113.45]) by webmail.destination.com (15.0.3 build 12) with ESMTP (SSL) id 202401151425221476 for <john.doe@destination.com>; Mon, 15 Jan 2024 14:25:22 +0000
Received: from a1-99.smtp-out.amazonses.com ([54.240.1.99]) by mx1.example.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Jan 2024 14:20:17 +0000
Date: Mon, 15 Jan 2024 14:20:15 +0000
X-Secure-Email-Gateway-Filtered: true

Key Points to Check

• SPF: Verify that the Sender Policy Framework (SPF) record is valid.
• DKIM: Ensure DomainKeys Identified Mail (DKIM) is correctly set up.
• Bounce Reports: Confirm there are no bounce reports indicating the email was rejected by any server.

Common Issues and Fixes

Rate Limiting

Ensure that your sending rate does not exceed the limits set by your email service provider or gateway.

DNS Configuration

Verify that your DNS records (SPF, DKIM, DMARC) are correctly configured to avoid email rejection or delay by recipient servers.

Blacklisting

Check if your sending IP or domain is blacklisted. Use online tools to check for blacklisting and follow their guidelines to delist.

Email Content

Ensure that your email content is not triggering spam filters. Avoid using excessive links, images, or spam-like language.

Conclusion

By following these steps, you should be able to diagnose and resolve most issues related to email delivery delays when using Descope. For persistent issues, please contact Descope support for further assistance.