I have a small system that sends about 15 email/day to my personal email account. I have set up the web form so that the users email is set as sender when I send the email to my inbox so it's easy for me to answer with just a reply. The problem is now that my IP is getting stuck in http://cbl.abuseat.org/ as a spam IP. My volumes are so low so I did not think this would be a problem and my messages contains no capital letters, no xxx-words or what I think are other problems. Just plain text with my users questions.
What can I do to prevent this. The mail server is on the same ip as my web server with the same domain, but the server that I'm sending my mails to is the one of my ISP. The server I'm using is hMailServer and it is basically default settings.