I just recently started having connection problems with Outlook 2007 to Exchange Server 2003 via RPC HTTP. My office has been using this connection method for a few years now. Now, the connection is not working. Outlook is saying “Microsoft Exchange is unavailable”. I checked the ports 80, 443 they are working. The webmail features of exchange is working properly. Employees that using basic TCP/IP connection are getting their mail. Did something change? Also, is there a better way to connect to Exchange Server?