From: Mail Delivery System <[email protected]> <[email protected]>: host mx1.domain.example[127.5.6.7] said: 550 5.1.1 <[email protected]>: Recipient address rejected: User unknown in virtual mailbox table (in reply to RCPT TO command)
If you do write to us, please at least bother doing it from an address that can be replied to. It’s very difficult to get the information you request to you otherwise.
The response that could not be delivered today is that your IP is included in a /24 listing that your Email Service Provider has allowed to go unattended for more than two years. Please talk to them about it.