Some posters are being deleted with this error message: The last reported
error was: 5.7.1 554 5.7.1 optonline.net is blacklisted.
I turned off the automatic delete feature for the list, but I'm confused about
this error. So someone with a non optonline address posts to the list which
contains 30 or so subscribers with optonline addresses. The poster is being
punished because those addresses are blacklisted? I don't have any blacklists
configured on the server, so I'm not sure where its getting its information.
Incoming does go through a barracuda appliance. Is something more sinister
happening here?