Email Sent from an External Mailer Is Blocked by Symantec Messaging Gateway or Email Security.cloud

Products

• Email Security.cloud
• Messaging Gateway

Issue/Introduction

Emails sent from an external mailer are being incorrectly flagged as spam by Symantec Messaging Gateway (SMG) or Email Security.cloud (ESS).

You believe these emails are legitimate and would like to:

• Understand why they were blocked.

• Request filter adjustments.

• Learn how to prevent similar issues in the future.

Environment

• Symantec Messaging Gateway
• Symantec Messaging Gateway for Service Providers
• Email Security.Cloud

Resolution

1. Message Blocked by Anti-Spam Rules

Symantec may, at its discretion, investigate and review messages that are mistakenly flagged as spam. If you believe your message is a false positive, follow the process below to submit it for analysis.

Submission Requirements

• Submit the original message as a .eml or message/rfc822 email attachment.

• Only one message per submission is allowed.

Submit To the Correct Regional Email Address:

Region	Submission Email Address
Americas	[email protected]
EMEA	[email protected]
APAC	[email protected]
Japan	[email protected]

 

Instructions for attaching messages are available for common email clients. For other clients, please refer to vendor documentation.

Important Notes

• No confirmation or feedback is provided for false positive submissions.

• Ensure the message is submitted in the correct format.

• If the issue persists, contact your administrator or Symantec Support.

---

2. IP Address Has a Negative Reputation

If your email-sending IP address is blocked due to a poor reputation:

Check Reputation:

Visit the IP Reputation Investigation Tool.

Request Review:

• If the IP has a negative reputation, click the “Investigate” link on the result page.

• Requests are usually processed within 24 hours.

• No direct feedback will be sent; the IP will simply be removed if it passes the review.

Additional Notes:

• This tool applies only to Symantec’s internal IP reputation system.

• It does not affect third-party blacklists or real-time blackhole lists (RBLs).

• Symantec reserves the right to deny requests based on analysis of mail traffic.

---

3. What Happens to False Positive Submissions?

Each submission is:

• Individually reviewed to identify the cause of the spam verdict.

• Evaluated to determine whether filter adjustments are necessary.

Note: Submission does not guarantee a change to Symantec’s spam filters.

---

4. Best Practices to Avoid Spam Classification

To help ensure your emails are not blocked or flagged as spam, follow these recommendations:

• Maintain List Hygiene:

  • Remove outdated or inactive addresses.

  • Clean addresses that bounce or show no engagement.

• Use Verified Email Lists:

  • Avoid third-party lists unless fully opt-in verified.

• Honor Opt-Out Requests Promptly:

  • Provide an unsubscribe mechanism and act on requests immediately.

• Implement Double Opt-In:

  • Require email confirmation before finalising subscriptions.

• Monitor Engagement:

  • Remove recipients who consistently do not open your messages.

• Leverage a Reputable ESP or List Management Provider:

  • Helps ensure list integrity and proper formatting.

---

If further assistance is required, please contact your mail administrator or raise a ticket with Broadcom Technical Support for further assistance.