These clients include Microsoft Outlook 2007 or Outlook 2010, Outlook for Mac, Mail.app in Mac OS X, iPhone, iPad and ActiveSync enabled phones. How Exchange's Autodiscover Works With Mail.app Autodiscover automatically configures profile settings for Exchange clients. Client IP is conveniently provided to the script in $_SERVER. The MAC address of a client (in the sense of the computer that issued the HTTP request) is overwritten by every router between the client and the server.
