This protocol assumes the client has previously logged on to the message store, as specified in [MS-OXCSTOR] section 126.96.36.199, and has acquired a handle to the Server object on which it is going to operate. Methods to open the object and acquire a handle are dependent on the type of object. For details about Message objects and Attachment objects, see [MS-OXCMSG]. For details about Folder objects, see [MS-OXCFOLD]. For details about Logon objects, see [MS-OXCSTOR]. Details about Stream objects are specified in this document.