Problems with Delivery, Reverse DNS, Mailing, and Razor2

If you notice issues with email delivery, such as receiving few responses or requests, it's often due to changes in configuration or other problems. Always check your mailing through a service if your delivery has deteriorated. You can usually find a solution there, except in the case of Razor. Other services can provide more or less adequate solutions.

There is a significant problem affecting a variety of accounts, necessitating a comprehensive examination of all the Sangrid accounts. The issue primarily involves old accounts with outdated domains and IP addresses that are part of the reverse DNS setup. This setup, especially the poor diagnostics and connections to incorrect domains, is leading to complications. Consequently, Google and other providers are either inadequately processing, suspending, or completely blocking the traffic. I remember sending something without reverse DNS, contributing to the overarching issue that went unnoticed. It's crucial to review all accounts with issues, particularly concerning Mailbox delivery.

Link Branding

Rewrite all tracking links to use your chosen domain, not Learn more
SPF for All IP Addresses
Always test your mailing every time you make changes or when you are in a new account and need to use old configurations to understand what works on the server.


When you are in Razor, you typically need to change the sending domain. You cannot just remove it and request delisting. Alternatively, from the outset, avoid sending bulk emails associated with transactional domain names.

Razor2 indicates a confidence level above 50%
cf: 100
Listed in Razor2 (

In my case, the problem was a specific combination of words in the email with legal terms, which apparently get blocked by spam filters. Completely rewriting the email solved this problem. However, you can test it by writing a simple text that you create yourself, then you will see immediately.