My e-mail clients connect to their Exchange Server using Internet Mail in Outlook 2000 and Outlook Express. They can send & receive mail from within the same global address book but not outside (ex:hotmail.com,etc.) I have (what I think) are the same settings at home & can send outside our global. The error message is the same as if I tried to send to an invalid e-mail address (“unknown recipient”). I travel around my state & am having the same probs everywhere. I’ve tried different versions of IE at each site. We’re all running MS Office Pro SP1.