Summary
Google Postmaster Tools reporting IPs not associated with your domain is a multifaceted issue primarily stemming from unauthorized use of your domain or misconfigured email authentication. Contributing factors include domain spoofing, shared infrastructure causing reputation bleed, authentication failures due to SPF/DKIM issues, and ineffective DMARC policies. Experts recommend thoroughly investigating SPF, DKIM, and DMARC records, actively monitoring DMARC reports, and promptly addressing discrepancies. They also caution against overly focusing on irrelevant IPs if the domain reputation is high. The information clearly indicates that unauthorized email is being sent using your domain name.
Key findings
- Unauthorized Use: Unexpected IPs often indicate someone else is using your domain to send email without permission.
- Spoofed Subdomains: Rogue emails from spoofed subdomains can harm your reputation, even if your main domain is properly authenticated.
- VPS Providers: Some IPs may be associated with VPS providers known for bad actors, affecting your reputation.
- Shared IPs: Shared hosting environments can lead to reputation issues due to the actions of other users on the same IP.
- Authentication Failures: Issues with SPF, DKIM, or DMARC can cause legitimate or unauthorized emails to appear as unauthorized, impacting deliverability.
- DMARC Ineffectiveness: A DMARC policy set to 'none' only monitors abuse and doesn't prevent unauthorized emails from being delivered.
- Overinclusive Reporting: GPT sometimes lists IPs involved in domain forging or forwarding, not necessarily direct misuse.
Key considerations
- Review SPF: Ensure your SPF records accurately list all authorized sending sources.
- Implement DKIM: Correctly implement DKIM signatures to authenticate your outgoing emails.
- Configure DMARC: Establish a robust DMARC policy (quarantine or reject) to handle emails that fail SPF and DKIM checks.
- Monitor DMARC Reports: Actively monitor DMARC reports to identify and address unauthorized sending sources.
- Investigate Authentication: Thoroughly investigate your SPF, DKIM, and DMARC setup for any misconfigurations.
- Monitor Reputation: Continuously monitor your domain and IP reputation using tools like Google Postmaster Tools.
- Investigate Discrepancies: Promptly investigate any unusual IP activity or discrepancies reported by Google Postmaster Tools.
- Assess Domain Reputation: Focus on addressing issues impacting your domain reputation and overall deliverability.
- Consider Source: Consider the possibility of legitimate, non-malicious causes for emails such as forwarding.
What email marketers say
10 marketer opinions
Google Postmaster Tools reporting IPs not associated with your domain typically indicates unauthorized use of your domain or issues with your email authentication setup. Several factors contribute to this, including domain spoofing, shared IP addresses, problems with SPF, DKIM, or DMARC configuration, and the use of subdomains. Continuous monitoring and prompt investigation are crucial for maintaining a healthy sender reputation.
Key opinions
- Domain Spoofing: Unauthorized entities might be sending emails using your domain without permission, harming your sender reputation.
- DMARC Issues: Incorrect DMARC setup, such as a 'none' policy or problems with subdomain coverage, can allow unauthorized emails to be delivered.
- Shared IPs: Using shared IP addresses, especially in hosting environments, can lead to reputation issues if other users engage in spammy behavior.
- Authentication Problems: Forwarded emails or incorrect SPF/DKIM configurations can cause legitimate emails to appear as unauthorized.
Key considerations
- Review DMARC: Ensure your DMARC policy is correctly configured to quarantine or reject unauthorized emails, not just monitor them.
- Monitor Reputation: Continuously monitor your domain and IP reputation using tools like Google Postmaster Tools.
- Investigate Discrepancies: Promptly investigate any unusual IP activity or discrepancies reported by Google Postmaster Tools.
- Implement Security: Implement and regularly review strict email security best practices, including SPF, DKIM, and DMARC.
Marketer view
Marketer from Email Geeks suggests that if Google has reported the IPs in GPT but has not sent DMARC reports, there might be issues with the DMARC setup, possibly involving spoofed sub-domains not covered by the DMARC record.
7 Nov 2022 - Email Geeks
Marketer view
Email marketer from EmailDeliverabilityBlog.com explains that continuously monitoring your domain and IP reputation using tools like Google Postmaster Tools is crucial. Regularly check for any unusual IP activity and investigate any discrepancies promptly to maintain a healthy sender reputation.
1 Jan 2023 - EmailDeliverabilityBlog.com
What the experts say
4 expert opinions
Google Postmaster Tools reporting IPs not associated with your domain can stem from various sources. Some IPs may be linked to VPS providers known for bad actors. GPT might also include IPs forging your domain or forwarding emails. Experts advise investigating SPF, DKIM, and DMARC records to identify unauthorized sending sources and monitoring DMARC reports to address flagged IPs, but also caution against excessive focus on IPs not directly related to your sending domain if your domain reputation remains high.
Key opinions
- VPS Provider Issues: Some IP addresses may be associated with VPS providers prone to abuse and bad actors.
- Over-inclusive Reporting: GPT can sometimes include IPs involved in domain forging or email forwarding, not necessarily direct misuse.
- Unauthorized Sending Sources: Unexpected IPs often indicate unauthorized use of your domain for sending emails.
- DMARC Importance: Implementing and monitoring DMARC reports are crucial for identifying and addressing unauthorized sending sources.
Key considerations
- Investigate Authentication: Thoroughly investigate SPF, DKIM, and DMARC records to pinpoint unauthorized sending sources.
- Monitor DMARC: Actively monitor DMARC reports to identify IPs sending emails on behalf of your domain.
- Assess Domain Reputation: Prioritize addressing issues impacting your domain reputation, rather than spending excessive time on unrelated IPs.
- Consider Source: Take into account the possible causes for emails such as forwarding or forging, which are not always malicious.
Expert view
Expert from Email Geeks shares that four of the listed IP addresses are Linode boxes and one is OVH, both of which are bottom-end VPS providers known for issues with bad actors.
3 Dec 2022 - Email Geeks
Expert view
Expert from Word to the Wise explains that implementing and actively monitoring DMARC reports is essential. These reports highlight which IPs are sending emails using your domain, allowing you to identify and address any unauthorized sending sources that might be causing Google Postmaster Tools to flag unexpected IPs.
18 Sep 2024 - Word to the Wise
What the documentation says
4 technical articles
Google Postmaster Tools reports IPs not associated with your domain when those IPs are either impersonating your domain or your domain is being used without proper authorization. This can arise from authentication issues, discrepancies between your SPF records and sending IPs, missing or invalid DKIM signatures, or a poorly configured DMARC policy. Proper implementation of SPF, DKIM, and DMARC is essential for preventing unauthorized domain use.
Key findings
- Impersonation: IPs sending mail impersonating your domain will be flagged.
- SPF Discrepancies: Mismatches between your SPF record and sending IPs trigger flags.
- DKIM Issues: Missing or invalid DKIM signatures result in suspicious IP reporting.
- DMARC Configuration: A weak or absent DMARC policy allows unauthorized domain use to persist.
Key considerations
- Verify SPF: Ensure your SPF records accurately list all authorized sending sources.
- Implement DKIM: Correctly implement DKIM signatures to authenticate your outgoing emails.
- Configure DMARC: Establish a robust DMARC policy to instruct mail servers on handling failed authentication checks.
- Address Authorization: Investigate and resolve any instances of unauthorized domain usage.
Technical article
Documentation from RFC Editor specifies that Sender Policy Framework (SPF) records should accurately list all authorized sending sources for your domain. If there are discrepancies between your SPF record and the IPs sending mail claiming to be from your domain, Google Postmaster Tools may flag these IPs.
20 Feb 2022 - RFC Editor
Technical article
Documentation from Google Support explains that Google Postmaster Tools might report IPs not directly associated with your sending domain if those IPs are involved in sending mail that impersonates your domain or if there are authentication issues where your domain is being used without proper authorization.
5 Mar 2022 - Google Support
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