2.2.1 Free/Busy Message
Free/busy data is represented as a set of properties that are set on a message in the public foldersmessage store. The message is referred to as the free/busy message. The location of this message is specified in section 188.8.131.52.2. Unless otherwise specified, the free/busy message conforms to a Message object, as specified in [MS-OXCMSG].