Some of my users periodically travel. When at some locations, not all, and they try to access thier e-mail on my Exchange 2003 server via OWA, they are repeatedly prompted for their password. Finally OWA opens with the folder list pane on the left, however the reading pane is empty and displays access denied. Can someone please tell me what is causing this? Are my users behind a Proxy or firewall at the locations where this happens? How can I get them access to thier e-mail with OWA?