Improving Email Deliverability from Your Server

If your emails are being filtered as spam or bouncing back, your server may have a poor email reputation. Here’s how to identify and resolve potential issues:

• Improving Email Deliverability from Your Server
• Diagnostics: Identifying the Problem
  • 1. Verify Your Server Isn’t Sending Spam
• Reputation Management: Improving Your Standing
  • 2. Check Your PTR Records
  • 3. Check for Blacklisted Mail IP
  • 4. Assess Your Mail IP Reputation
• Advanced Options: Further Steps
  • 5. Address Microsoft-Specific Reputation Issues
  • 6. Update Your Mail IP
• Frequently Asked Questions (FAQ)
• Conclusion and Next Steps

Improving Email Deliverability from Your Server

If your emails are being filtered as spam or bouncing back, your server may have a poor email reputation. Here’s how to identify and resolve potential issues:

Diagnostics: Identifying the Problem

1. Verify Your Server Isn’t Sending Spam

Ensure your server isn’t actively sending spam before troubleshooting further. Here's how:

• For cPanel servers: Use WHM's "View Sent Summary" to identify accounts sending high volumes of emails or experiencing a high number of failures.
• For advanced users with SSH access: Check the email logs at /var/log/exim_mainlog for details on email activity.
• For Plesk servers: Access logs at /usr/local/psa/var/log/maillog.

If you cannot locate the issue, contact support for assistance.

Reputation Management: Improving Your Standing

2. Check Your PTR Records

A Reverse DNS (RDNS or PTR) record maps your server's IP address to a hostname. To verify:

• Use MXToolbox Reverse Lookup.

If the RDNS doesn’t point to your server’s hostname, contact support to have it corrected.

3. Check for Blacklisted Mail IP

If your IP is blacklisted, it could be due to spam activity. Here's how to check:

• Use MXToolbox Blacklist Checker.

If listed, follow the blacklist’s delisting instructions or contact support for help. Ensure your server is no longer sending spam before requesting delisting.

4. Assess Your Mail IP Reputation

Beyond blacklists, some services track IP reputation. Check your server’s reputation here:

• Talos: Talos Reputation Center. Submit a ticket if your IP has a poor reputation.
• Sender Score: Sender Score. Check if mailbox providers view your IP as reputable.
• TrendMicro: TrendMicro Email Reputation Services. Submit a delist request if necessary.
• Symantec: Symantec IP Removal. Fill out their form after checking your reputation.

Advanced Options: Further Steps

5. Address Microsoft-Specific Reputation Issues

If emails are being rejected by Microsoft systems, request delisting via this form.

6. Update Your Mail IP

In extreme cases, changing your server’s sending IP can help.

• For cPanel: Follow this guide: How to Configure the Exim Outgoing IP Address.

Frequently Asked Questions (FAQ)

Q: What is a PTR record, and why does it matter?

• A PTR (or Reverse DNS) record ensures that an IP address resolves back to a hostname, verifying the legitimacy of the server sending emails. Missing or incorrect PTR records can cause emails to be flagged as spam.

Q: How long does it take to be removed from a blacklist?

• Delisting timelines vary depending on the blacklist provider. Some update within hours, while others may take several days.

Q: What are the key reasons emails are marked as spam?

• Common reasons include poor email content, lack of SPF/DKIM records, sending too many emails in a short time, or a compromised server sending spam.

Q: What is the difference between a blacklist and an IP reputation?

• A blacklist is a definitive "blocklist" that prevents email delivery, while IP reputation is a score that influences whether emails are flagged as spam by mailbox providers.

Conclusion and Next Steps

Following these steps should resolve most email deliverability issues. Regularly monitor your server’s email activity and reputation to prevent future problems. If you’re unable to resolve the issue, our support team is here to help.