Trying to get another host to send trough ISPConfig, I have found the following recommendation in an old thread; It appears common sense but I have tried it unsuccessfully: I have set up the client host to log in to a mailbox, to which it supplies the valid credentials. The client hosts connection attemps are rejected, but not because of invalid credentials, because of rejection of the client host itslef. The log on the sender's side says (ip address voluntarily hidden). I cannot use the sender's IP as authenticator, because it is a consumer variable IP address. Therefore I need to rely on mailbox credentials, but it does not work. What could the problem be ?
