Who is blocklisting my IP?
Web hosting providers maintain blocklists (lists of banned IP addresses). There is no central source of IP blocklists, and if your IP is on multiple blocklists your email may be stopped at any point along the internet before arriving at its destination.
It’s simple enough to do a search for who is blocklisting your IP. There are numerous search tools available to help you figure out the blockages.
Each provider has different standards for listing and delisting IP addresses. But one constant is that if you have a virus or malware on your computer, it will be actively trying to communicate with other computers and be defined as an “attack” computer, resulting in your IP address being blocked.
Other reasons for blocklisting include too large a volume of mail, or messages that have spam characteristics. If you have a DHCP IP address (a variable IP address typically used for residential connections), it may be that a computer previously associated with that IP address was a spammer, so you are blocked even though you did nothing wrong.
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