Anti-Spam Blocklists: What Are They and Why Do They Cause So Many Problems

In this article, Stefan Pollard explains how to address issues with blocklists, how to resolve them, and how to restore both your sender reputation and delivery rates.

How do you know if you're on a blocklist?
The fastest way is to use a blocklist checker that queries multiple lists at once. Many e-mail service providers (ESPs) give their clients tools, sometimes through partnerships with reputation companies, to check if they're currently listed. These include EmailAdvisor's Blacklist Monitor, Return Path's Sender Score, and Habeas' RepCheck.

These two free sources offer domain or IP look-up services: SURBL and DNSstuff.

If you find your sending IPs or domains listed, you should also find a link to the blocklist, where you can look for evidence for the listing. Monitoring your bounce logs can also turn up block messages, which often provide the blocklist name and URL.

Continue reading here to find out what you need to do to get off a blocklist.