Don’t you hate it when you send an email, and it bounces back? You just lost a lead and likely earned yourself a spot on a blacklist.  Now, you have to deal with the hassle of removing your IP from the list so your emails can reach inboxes again. This process can take a few days, and in that time, the trust you’ve built with your audience erodes. Worse, you may not even know why your emails are bouncing if you don't fix email reputation. This article will help you identify the cause and quickly remove your IP from blacklists, so you can restore deliverability and regain lost trust.

Inframail provides a valuable solution to help you achieve your goals, like quickly removing your IP from blacklists. Our email infrastructure gets to the bottom of your deliverability issues so you can restore trust and get back to business.

Table of Contents

• What Is an Email Blacklist?

• What Causes an IP to Get Blacklisted?

• How IP Blacklist Removal Works

• Start Buying Domains Now and Set Up Your Email Infrastructure Today

What Is an Email Blacklist?

An email blacklist is a dynamic list of IP addresses that have been flagged for sending spam. Email service providers, free mailbox providers, and anti-spam vendors use artificial intelligence from blacklists to protect their users from spam and other malicious activity. Your server IP address can be placed on a blacklist by:

1. IPS Hitting More Than The Permissible Threshold Level Of Spam Traps 

A spam trap is an email address set up and monitored by ISPs to catch spammers sending unsolicited emails. Getting caught in this can damage your email reputation, eventually getting you blacklisted.

2. Spam Complaints 

Email recipients can mark your IP address as spam if you send them unwanted bulk or suspicious emails. Your IP address develops a bad reputation, and in the long run, your IP can get blacklisted as you are seen as a potential threat to the safety of others. 

3. Hacked IP and IP Spoofing 

Hackers can hack and start using your IP address for illegal activities. This can get your IP blacklisted even though you haven’t done anything wrong or suspicious. IP spoofing occurs when an attacker fakes his/her IP address to impersonate someone else on the internet to avoid getting caught. This can get you blacklisted. 

4. A Sudden Spike In Email Volume 

When a large number of emails are sent in a short duration, it signals spamming behavior by email providers, thus leading to blacklisting. 

The Lowdown on Different Types of Blacklists 

Third parties own external blacklists. Mailbox providers may use an external blacklist to identify spammers. If your IP were listed on one of these lists, you must contact the third party for manual removal rather than a mailbox provider who blocked you. 

Related Reading

• IP Address Reputation
• Blacklisted Email

What Causes an IP to Get Blacklisted?

Technical Reasons: Why Does an IP Address Get Blacklisted?

Technical listings happen because of mail server configuration issues. For instance, if your reverse DNS records are missing or incorrect, your emails may be marked as spam by ISPs. The same goes for missing or inaccurate banner greetings. Another common technical reason for blacklisting is that the mail server operates within a suspicious range of IP addresses. If the mailing server shares an IP address with other senders, and one of them has a bad reputation, your emails may also suffer. 

Policy Reasons: Why Does an IP Address Get Blacklisted?

Policy listings occur when the receiving server does not wish to accept emails from certain countries or ISPs. This can happen if the server has a history of not handling “unsubscribe” requests. If you’re sending emails to recipients in that country, and the server identifies your IP address as belonging to the suspicious range, your emails may get filtered, and you could even get blacklisted.

Evidence-Based Reasons: Why Does an IP Address Get Blacklisted?

Evidence-based listings are those where the server has received direct (or indirect) evidence that the sending IP address has been involved in sending unsolicited emails. In these cases, the receiving server may have an actual complaint about the emails sent from your IP address. The complaints can come from users or automated spam-tracking tools. Either way, the evidence points to the fact that the sending IP address is involved in sending spam. 

How Does Being Blacklisted Affect Email Deliverability?

Mail providers keep their users safe from spam, and they do so by carefully choosing which blacklists they use. When you send an email, the receiving server checks the IP address it was sent from against its collection of blacklists. If the sender’s IP address is listed on a blacklist that the receiving server uses, the mailbox provider might: 

• Filter the email as spam

• Bounce the email

• Drop it entirely

Two Scenarios: What to Do If Your IP Address Gets Blacklisted

Two scenarios involve different actions on your part: 

Scenario 1: 

Email service providers (ESPs) and SMTP relay services manage IP address reputation, handling blacklisting issues. Users should generally rely on these services to resolve such problems. High-volume senders can request dedicated IP addresses to build their sender reputation and avoid impact from other senders' activity.

Scenario 2: 

If you're sending email via your own SMTP server, first determine the severity of the blacklist impacting your IP. Minor blacklist listings with no deliverability issues can be ignored. Primary blacklist listings require remediation. To identify the cause, check your IP address on the blacklist's website. Following their removal procedures may involve correcting DNS records and SMTP banners, which may require technical expertise. Enhance network security by: 

• Scanning for viruses

• Updating systems

• Securing routers

• Strengthening passwords

Does a Blacklisted IP Affect Deliverability?

If you are sending mail from a blacklisted IP address, you will probably receive a bounce message indicating that your email was rejected because you’re listed on a blacklist. In most cases, the bounce message includes the name or URL of the blacklist. An example of this type of message is: “Message rejected due to IP [1.1.1.0] listed on RBL [X]” If you do not see this type of message in your bounce notifications, it’s unlikely that the blacklist is impacting your deliverability.

Related Reading

• How to Improve IP Reputation
• Google Blacklist Removal
• How to Get Off Email Blacklist
• Blacklist Removal Tool

How IP Blacklist Removal Works

1. Perform a Domain Blacklist Check to Identify the Blacklist and the Reasons

Despite best efforts, email blacklist inclusion can occur. To address this, first confirm your status using multiple blacklist checkers, like Smartleads tool. Then, identify the reason for blacklisting, as this guides remediation. Common causes include: 

• Spam content

• Compromised servers

• Shared hosting issues

Patience and careful action are crucial for successful delisting.

2. Address and Resolve Issues Promptly

After identifying the reasons for your domain being blacklisted, it's imperative to address and fix these issues before proceeding with the delisting process. Take this step seriously, as simply requesting delisting without resolving the underlying problems can lead to repeated blacklisting. It is also important to note that once your domain is blacklisted and you do not take adequate measures to delist it, eventually your IP too may be flagged. 

3. Send Blacklist Removal Request

When submitting a removal request for email blacklists, it's essential to understand that the process can vary significantly based on the type of blacklist and the policies of the listing organization. Major email blacklists and Real-Time Blackhole Lists (RBLs), such as Spamhaus, SpamCop, and Barracuda, each have their procedures and criteria for delisting. Some may require a simple removal request through their website or email, while others may have specific forms or verification processes. Below is a list of popular RBLs and a list of how to delist from each. 

Delisting from Spamhaus

Spamhaus is one of the most recognized and stringent email blacklists. If your domain is listed on Spamhaus, follow its specific delisting process. 

This typically involves: 

• Visiting the Spamhaus website and checking the listing details. 

• Spam Filters: Addressing the issues that caused the listing, such as stopping spamming activities, securing your email servers, and ensuring compliance with their policies. 

• Requesting delisting through Spamhaus's website and providing evidence that the issues have been resolved.

Delisting from Barracuda

Barracuda maintains its own blacklist and reputation system. 

To delist from Barracuda: 

• Visit the Barracuda Central website and check your domain's reputation. If listed, investigate the reasons and take corrective actions, such as removing spammy content or securing your email infrastructure. 

• Submit a delisting request through Barracuda's delisting portal, providing the necessary details and evidence of corrective actions. 

Delisting from SpamCop

SpamCop automatically blocks and unblocks IP addresses. If SpamCop continues to receive reports of spam originating from the networks you are responsible for, those networks will remain listed. If no further reports are received, SpamCop will automatically delist your IP address after 24 hours. It's important to note that if the reports received by SpamCop relate only to web hosting for the spammer, they do not count towards the blocking list. SpamCop's email filters specifically consider complaints related to spam sourcing. Suppose you have recently closed an open relay on your network or removed a botnet infection. In that case, it is advisable to check and notify other blocking systems, such as Spamhaus CBL (Composite Blocking List), but only if they have detected and listed your server. 

SURBL

SURBL (Spam URI Real-time Blocklists) focuses on detecting spam based on URLs included in email messages. 

If your domain or URL is listed on SURBL, you can request delisting by: 

• Visit the SURBL website and search for your domain or URL. 

• Reviewing the details of the listing to understand why you were listed. 

• Correcting the issue that caused the listing (such as removing malicious URLs or correcting DNS records). 

• Sending a delisting request via the contact form or email address provided on the SURBL website, including relevant details and proof of correction. 

Microsoft 

You can use their delist portal from their blocked senders list for Microsoft 365’s delisting process. 

Here's how the process generally works: 

Microsoft 365 uses a blocked senders list to safeguard users from spam, spoofing, and phishing threats. If your IP address is flagged as a potential risk to their service, it may be added to this list to prevent email communication with Microsoft 365 organizations. 

To request removal from the blocked senders list: 

• Visit the Microsoft 365 delist portal. 

• Follow the instructions provided to submit a delisting request. 

• Provide the necessary details, such as your IP address and any relevant information regarding the removal request. 

• Microsoft will review your request and take appropriate action based on their delisting policies. 

• You can visit Microsoft’s official delist portal for more detailed information and access the delist portal. 

• This portal will guide you through the steps necessary to request removal from Microsoft 365’s blocked senders list effectively. 

Other Blacklists

Each blacklist may have its delisting procedures and requirements. 

It's essential to: 

• Check the specific blacklist's website for delisting instructions. 

• Follow their guidelines meticulously, often providing evidence of remedial actions and compliance with email best practices. 

• Monitor your domain's reputation post-delisting to ensure continued compliance and avoid future listings. 

4. Take Preventive Measures

Once your domain is successfully delisted, it's essential to implement preventive measures to avoid future blacklisting. This includes maintaining a clean email list, using authentication methods like SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail), regularly monitoring your email sending practices, and promptly addressing any reports of abuse or spam. Let’s talk about each one of them in detail: 

Maintain a Clean Email List

Regularly clean your email list by removing invalid or inactive email addresses. Implement double opt-in procedures to ensure subscribers genuinely want to receive your emails. Honor unsubscribe requests promptly to reduce the risk of recipients marking your emails as spam. 

Use Authentication Methods

Implement SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail) to authenticate your email messages. Ensure that your DNS records are correctly configured to reflect these authentication mechanisms. Consider implementing DMARC (Domain-based Message Authentication, Reporting & Conformance) to monitor and enforce email authentication policies. 

Monitor Email Sending Practices

Regularly monitor your email sending practices to detect any anomalies or signs of abuse. Use email analytics to track engagement metrics and adjust your email campaigns accordingly. Be vigilant for any reports of abuse or spam and address them promptly to mitigate potential blacklisting risks. 

• Build an email cadence: This refers to the frequency of sending emails to subscribers. A well-planned email cadence ensures that your messages are delivered consistently to your audience. Consistency in email frequency to different user segments will lead to maximum engagement and keep your users happy. 

• Monitor reputation: Use email reputation monitoring services like Sender Score to stay informed about your sender score and take preemptive action if necessary. 

Secure Your Email Infrastructure

Ensure your email servers are secure and up-to-date with the latest security patches. Implement strong password policies and consider using two-factor authentication (2FA) for email accounts. Monitor for unauthorized access or suspicious activity that could indicate a compromise. 

Educate and Train Staff

Educate employees on email security best practices, including recognizing phishing attempts and avoiding common pitfalls. Conduct regular training sessions to reinforce the importance of maintaining a reputable email sending reputation. To minimize risks, establish clear policies and procedures for handling customer data and email communications. 

Engage in Responsible Email Marketing

Avoid purchasing email lists or using questionable sources to acquire email addresses. Follow best practices for email marketing, such as including an explicit opt-out mechanism and respecting recipients' preferences. Segment your email list to send targeted and relevant content, improving engagement and reducing the likelihood of spam complaints. 

Monitor and Respond to Feedback

Monitor feedback loops and spam reports provided by email service providers or blacklist administrators. Respond promptly to any complaints or issues raised by recipients to prevent escalation. Use feedback to improve your email practices continuously and maintain a positive sender reputation.

Start Buying Domains Now and Set Up Your Email Infrastructure Today

Inframail revolutionizes cold email infrastructure with unlimited inboxes at a single flat rate. With Microsoft-backed deliverability and dedicated IP addresses, we help scale their outreach efficiently: 

• Agencies

• Recruiters

• SDRs 

Forget About Technical Setups

Inframail streamlines the entire process. We handle the complex infrastructure setup while you focus on reaching more prospects. Whether you're an agency looking to scale outreach, a recruiter connecting with candidates, or an SDR driving sales, Inframail provides a robust email infrastructure without the usual technical headaches and per-inbox costs. Start buying domains now and set up your email infrastructure today with our email infrastructure tool.

Related Reading

• Microsoft Blacklist
• Remove Domain from Blacklist
• Check if Email Is on Blacklist