SuperTool, offered by services like MXToolbox, is a comprehensive tool for checking domain and IP blacklist statuses. It scans various real-time blacklists (RBLs) to see if your domain or IP is flagged, which can help troubleshoot email deliverability and reputation issues.

What Is a Blacklist Check with SuperTool?

  • Purpose: Identifies if your domain or IP is listed on any spam or reputation blacklists.
  • Functionality:
    • Scans major blacklist databases (Spamhaus, Barracuda, SpamCop, etc.).
    • Provides information about why the domain/IP is flagged.
    • Offers delisting guidance if flagged.

How to Use SuperTool for a Blacklist Check

1

Access MXToolbox SuperTool

https://mxtoolbox.com/SuperTool.aspx
2

Enter Your Domain or IP

Input your domain name (e.g., example.com) or IP address (e.g., 123.45.67.89).

3

Select "Blacklist Check"

From the dropdown, choose Blacklist Check or let the tool auto-detect issues.

4

View Results

The tool will:

  • List all blacklists checked.
  • Highlight any blacklists that flagged your domain or IP.

What to Do If You Are Blacklisted

Investigate the Cause

1

Check Email Logs

  • Identify spam or unauthorized activities from your domain/IP.
  • Use commands like:
  • For Postfix:
    sudo tail -f /var/log/mail.log
  • For Exim:
    sudo tail -f /var/log/exim_mainlog
2

Scan for Malware

Use tools like ClamAV to scan your web server for malicious files.

3

Verify Email Authentication

Ensure SPF, DKIM, and DMARC records are correctly configured.

Resolve Issues

Remove Spam Sources

  • Disable compromised accounts and reset passwords.
  • Remove malicious scripts or files from your server.

Set Up Email Authentication

  • SPF: Specifies which mail servers can send emails for your domain.
v=spf1 include:_spf.google.com ~all
  • DKIM: Adds digital signatures to validate email integrity.
  • DMARC: Defines policies for email authentication failures.
_dmarc.example.com TXT "v=DMARC1; p=quarantine; rua=mailto:reports@example.com"

Limit Outbound Emails

Restrict the number of emails sent per hour to prevent spam-like behavior.

Request Delisting

1

Visit the Blacklist Provider Website

The SuperTool results will often include direct links to the blacklist provider removal page.

2

Submit a Delisting Request

Provide details about the resolved issue.

Example providers:

  • Spamhaus: Removal Center
  • Barracuda: Delisting Request
  • SpamCop: Blacklists

Prevent Future Blacklisting

Monitor Your Reputation

MXToolbox Monitor

Continuous monitoring of your blacklist status.

Google Postmaster Tools

Monitor your domain email reputation.

Microsoft SNDS

Smart Network Data Services for reputation monitoring.

Implement Security Best Practices

Secure Email Accounts

Enforce strong passwords and enable 2FA.

Regular Malware Scans

Automate scans with ClamAV or similar tools.

Rate Limit Outgoing Emails

Prevent excessive or spam-like email sending.

Ensure Proper Server Configuration

  • Check for open relays:
    • telnet mail.example.com 25
  • Disable relaying for unauthorized users.

Example Use Case

Scenario: Your emails to Gmail and Yahoo are bouncing back, and MXToolbox indicates your IP is listed on Spamhaus.

Steps Taken:

  1. Check Logs: Found a compromised email account sending spam.
  2. Resolve Issues: Disabled the account and reset its password. Updated SPF, DKIM, and DMARC records.
  3. Request Delisting: Submitted a delisting request to Spamhaus with evidence of issue resolution.
  4. Monitor: Set up email alerts for future blacklisting.

Benefits of Using SuperTool

Comprehensive Checks

Scans multiple blacklists at once.

Delisting Assistance

Provides links and guidelines for delisting.

Reputation Monitoring

Helps maintain your email deliverability and domain reputation.

MXToolbox SuperTool is a valuable resource for identifying and resolving blacklist issues. Regularly monitor your domain and IP reputation, maintain strong email security practices, and address any issues promptly to prevent future blacklisting.