An explanation of blacklists
Blacklists are used by receiving networks to evaluate the reputation of an IP address and/or domain. They're run by anti-spam groups and the majority of blacklistings result from sending Unsolicited Bulk Emails (UBE) to addresses that never requested them. You can read more about traps and blacklists in our article.
It is very important that your blacklist stays clean because there are many blacklist providers in existence, some of which carry more weight in the community than others.
How to deal with blacklisting
The first step to determining whether you have been blacklisted is to check on any of the following websites:
If your domain appears as blacklisted, we recommend you contact our Delivery team immediately. The best way to get this listing removed is to find out what caused it in the first place. If you want to avoid any further blacklistings on your list, send a reconfirmation email to all your recipients. This should be done every few months depending on how often you send emails and how big your list is.