Product Updates

Announcing — IP/Domain Blocklist Checker and Delisting Service

IP/Domain blocklists (formerly also known as blacklists) began appearing relatively early in terms of internet history. The first ones served a dual purpose; they blocked spam emails, but they also educated ISPs and website operators about the problems associated with spam.

Over the last 20 years, hundreds of blocklists have appeared, each with its own criteria for inclusion, rules for delisting, and standards. Some include only individual domains, but others may include an entire ISP if it has a history of harboring spammers.

However, one thing that most blocklists have in common is a lack of transparency. A fledgling entrepreneur or even a large corporation may never know about an appearance on a blocklist. If they find out they have been blocked, it can take weeks or even months to discover why and correct the issues. Until now.

Meet our lookup service – The one-of-a-kind IP/Domain Blocklist Checker and Delisting Service

Why Blocklists Are Needed

Initially, spam was little more than junk mail sent electronically. However, there was a lot of it. It seems that millions of people fervently believed that billions of other people truly needed their products or wanted to know what the senders thought. It was common for the holder of an email account to receive dozens or even hundreds of spam messages every day, making it time-consuming and difficult to find legitimate emails.

Over time, advances in technology allowed spammers to become even more insidious. Botnets can now deliver spam messages as well as malware and a variety of scams by taking over and manipulating computers and entire networks. The botnets can use hacked email accounts and the IP addresses of the networks and computers it has infected to generate billions of disruptive emails. Some are used to launch a denial-of-service attack. For example, in February 2010, over 300 websites were hit with DDoS attacks generated by the Cutwail botnet, according to, including the FBI, PayPal, the CIA, and Twitter.

How Blocklisting Affects Legitimate Companies

Marketing professionals state that email is their most profitable marketing channel, returning approximately $40 on every dollar spent. However, if emails are being sent to the recipient’s spam folder or blocked completely, the ROI will obviously be decreased significantly. Unfortunately, it is not all that difficult to land on a blocklist. An employee can unknowingly introduce a virus by opening an email, a customer may violate use policies out of ignorance, or a hacker can hijack a system to mask illegal activities.

Although this can have a substantial impact on retailers, even nonprofits can find themselves on blocklists. According to the Chronicle of Philanthropy, more than 12 percent of emails sent by nonprofit organizations never reach an inbox, reducing email fundraising totals by up to 14 percent. Many recipients may be marking the emails as spam, but blocklisting can sometimes be triggered if the ISP notices that emails are never opened or are deleted without being opened.

How To Resolve Blocklisting Issues

Identifying the issues that led to the blocklisting can be complicated enough, but securing removal from the blocklist can add even more layers of complexity.

Corporations who manage their own email services, as well as email service providers, can benefit from Abusix Mail Intelligence, our latest service designed to give email operators better peace of mind, control, and visibility.

Our service clubbed with Lookup-Service can help you find and correct issues related to blocklists.

Abusix provides full visibility into why the IP/domain was blocklisted – you will know what we know. And you get the tools to delist once actions are taken to remediate the issue. Contact us to learn more, or sign up for a free trial today.

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The quickest way to get in touch with the team is via our online chat feature at the bottom right of this page. Alternatively, feel free to email us at [email protected] or send us a message via our form.

Is your IP blocked?
To get that resolved, please use our lookup-service and follow the instructions in order to delist your IP/domain.