I have setup Listserv 15.5 on a Windows 2003 Enterprise server. We are using Exchange 2003. My account is admin in Listserv. I subscribed to both closed and open lists. When I post a message to an open list using the web interface, I get this error via email: Yo do not have permission to send to this recipient. <Listsrv.domain.com #5.7.1> I can post the message via email with no problem. If you have suggestions, please let me know. Thank you. A.