Hope you're getting this Thomas. I found this message whilst searching for a solution. I too get this error message. I've used TCP View and nothing is shown as using port 80. I do have more than 1 published server on different external addresses (all bound to the same card) using port 80 but surely that's OK??? I'm getting some strange things happening and I know you won't be able to be specific to my case but I'll tell you anyway. One minute everything works and then for no apparent reason, external email will stop coming in. ANother time, outgoing web access might fail and then another time, incoming web access might fail. There seems to be no logic to any of it. The only solution is to stop and restart the services and wait until it decides to go again. I wondered whether the above error may be the cause because I've also seen it referring to port 25 which could explain the email problems.