About Blacklist
The blacklist check compares the IP address of a mail server to more than 70 DNS-based email blacklists. (Usually referred to as RBL, DNSBL, or Realtime Blacklist). Certain emails you send could not be delivered if your mail server has been blocked. Blacklists of emails are a popular method of lowering spam. Start with an MX Lookup if you are unsure of the address of your mail server. Alternatively, just send contact@dnsloader.com an email.