Thank you for contacting the listing removals team.It appears that this IP is listed because the mail server is misconfiguredand/or it is also sending spam to our spamtraps.Usually, the misconfigurations we detect are easily rectified found.After fixing it, please open a new ticket to let us the solution used.Possible causes:1- Using a bare host name like "localhost" or "mail" or some windows default,2- using a bare IP address,3- using a reserved domain such as "example.com",4- using a domain that should not exist like "localdomain",5- using a domain that belongs to someone else,6- using a domain that does not exist such as a private internal one.Any attempt to remove this without fixing the issue will simply resultin the near immediate re-listing for exactly the same reason.Due to the enormous number of possible devices, it is not possible toprovide instructions or solutions.This is probably a nusoft firewall, you might have to upgrade it.Your understanding is appreciated.