IP Blacklist Check

IP blacklist check (RBL)

The service checks an IP address against four of the most influential blacklists at once: Spamhaus ZEN, SpamCop, Barracuda and SORBS. These are the databases half the internet's mail servers consult when deciding to accept or reject your email.

If mail from your server suddenly stops arriving — an RBL check should be the first step. You can get listed via an infected site on the same server, a hacked mailbox or a bad IP "inheritance" from the previous owner. Each database has its own delisting procedure on its site — after fixing the cause, removal takes from hours to a couple of days.