I've been having some issues with mail coming from my ISPConfig 2 box that it is either not received or goes into the spam folder for example in Yahoo mail or Comcast. Users are reporting complaints that their recipients are not receiving their mail. Especially when sent from round cube mail. I just checked my IP against spamhaus, etc. it's not listed. Do you have any suggestions as to what I should be looking into to resolve this issue?
Make sure that a reverse dns record for your ip exists and that it is identically to the server hostname and the hostname in your postfix configuration.
