When someone is blacklisted (or blackballed), it means that he or she is put on a list of individuals and organizations which have been singled out as deserving of some sort of denial or punishment, with the assumption that they deserve such treatment because of their behavior.Why is my domain blacklisted?
If enough of those domains' users mark mail received from a particular IP address as spam, the RBL can blacklist that address, blocking all mail from it. If your mail is being bounced, it's possible that an RBL service has blacklisted your domain's IP address.Why is my IP address blacklisted?
If your IP address was blacklisted, it means that it was reported to one of known DNSBLss as a suspicious IP sending spam or having some other dangerous activity. Except spamming, the following popular reasons for blacklisting IP are: Virus activity.