What causes an IP to be listed on the Spamhaus Block List (SBL) and how can it be resolved?
Summary
What email marketers say13Marketer opinions
Marketer from Email Geeks explains that the address itself might not be dangerous; plenty of them will be regular people's real addresses who did not sign up and are victims of a bad actor + your insecure form
Marketer from Email Geeks shares that the reason in the listings..."Spammers have abused an insecure webform sometime in the past, and used the victim's email address. As a result, the victim is being "listbombed" with transactional messages and bulk email campaigns. For additional information, please see this link: <https://www.spamhaus.org/news/article/734/subscription-bombing-coi-captcha-and-the-next-generation-of-mail-bombs>"
Email marketer from SendPulse answers that to remove your IP from a blacklist, you must identify the blacklist, understand their removal policy (often found on their website), and follow their specific delisting process, which usually involves filling out a form and demonstrating that you've resolved the issues that caused the listing.
Email marketer from GlockApps explains that common reasons for ending up on the SBL include spam traps, high complaint rates, insecure web forms, and malware infections. Regular monitoring of your sending reputation and infrastructure is essential.
Email marketer from Webmaster Forum user User42 responds that using a shared IP can increase the risk of blacklisting if other users on the same IP engage in spammy behavior. Monitoring the IP's reputation and considering a dedicated IP if you send a high volume of emails is recommended.
Marketer from Email Geeks explains that in this case, COI is clearly not being used, because this is the second time this IP has been listed for the exact same trap.
Email marketer from Mailjet shares that reasons for IP blocklisting include high spam complaint rates, sending to invalid email addresses (resulting in high bounce rates), and compromised accounts used to send spam. Maintaining clean lists and good sending practices are crucial.
Email marketer from Reddit user u/EmailPro2020 shares that maintaining a good sender reputation involves consistently sending valuable content, respecting unsubscribe requests, and avoiding spam trigger words. Engaging with your audience and segmenting your lists can also help improve deliverability.
Email marketer from ZeroBounce shares that spam traps are email addresses used to identify spammers, avoiding them means practicing good list hygiene, using double opt-in, and regularly cleaning your list by removing inactive subscribers. Always get permission before sending emails.
Email marketer from Validity shares that to avoid blacklists, focus on building a permission-based email list, implementing robust email authentication, monitoring your sending reputation, and promptly addressing any complaints. Regular list hygiene is also crucial.
Email marketer from Neil Patel Blog shares that improving your IP reputation involves sending emails to engaged subscribers, authenticating your email (SPF, DKIM, DMARC), and consistently monitoring your sender score. This proactive approach minimizes the chances of being added to blocklists.
Marketer from Email Geeks shares that if someone successfully enters a bad email address, it will drop out when COI fails.
Email marketer from Litmus explains that proper email authentication (SPF, DKIM, DMARC) is crucial for establishing your legitimacy as a sender and preventing your emails from being flagged as spam. It helps ISPs verify that your emails are actually coming from you.
What the experts say3Expert opinions
Expert from Word to the Wise explains that steps to maintaining IP health include: Monitoring feedback loops, keeping low complaint rates, and ensuring proper list hygiene.
Expert from Word to the Wise, Laura Atkins, shares that IP reputation is influenced by factors such as sending volume, spam complaints, and engagement metrics. Consistently low complaint rates and high engagement improve reputation and reduce the likelihood of blacklisting.
Expert from Spamresource shares that you can check if you are on a blocklist by going to their website and doing a lookup for your IP/domain. Then it will give you specific advice and a link to help remedy the issue.
What the documentation says6Technical articles
Documentation from Dmarc.org explains that DMARC builds upon SPF and DKIM to provide a mechanism for email senders to indicate that their messages are protected by these authentication methods, and instructs receiving mail servers on what to do if authentication fails, helping to reduce phishing and spoofing.
Documentation from Digital Ocean explains that to prevent IP blacklisting, implement strict email authentication protocols (SPF, DKIM, DMARC), monitor your sending reputation using tools like Sender Score, maintain clean and engaged email lists, and promptly address any abuse complaints.
Documentation from Spamhaus.org explains that the delisting process involves identifying the specific Spamhaus list your IP is on, understanding the reason for the listing, and following the delisting instructions provided on their website, which may involve submitting a request and demonstrating that the issue has been resolved.
Documentation from Spamhaus.org explains that an IP address can be listed on the SBL for various reasons, including sending spam, hosting spambots, or being part of a network that facilitates spamming activities. These listings aim to protect internet users and email systems from unsolicited and malicious emails.
Documentation from RFC-Editor.org explains that Sender Policy Framework (SPF) is an email authentication method designed to detect forging sender addresses during the delivery of email. SPF allows receiving mail servers to verify that mail purporting to come from a specific domain is authorized by that domain's administrators.
Documentation from Microsoft explains that if your IP is blocked, you should first determine the reason for the block, often found in the bounce message or notification from the blocklist provider. Then, follow the specific remediation steps outlined by that provider, which may include filling out a delisting request form.