New-User Profiles, Multiple Concurrent Sessions
One important capability that is available in CDO 1.2 but not in extended MAPI is the dynamic creation of new-user profiles. Typically, new users of client-side applications have a MAPI profile stored locally, but for their server-based applications they have none. For such applications, CDO 1.2 supports the dynamic creation of a new-user profile with information obtained through prompting for user name and password. This feature is important in Web-based or roaming-user applications where MAPI profiles cannot be guaranteed to be available on the local machine.
Through its support for multiple concurrent sessions, CDO 1.2 can handle a large number of users, whether an application is a desktop-based solution developed with the Visual Basic development system or a sophisticated Web-based solution. A related CDO 1.2 feature is its ability to use existing mail client sessions. For example, client-side applications developed with CDO 1.2 can piggyback on Outlook sessions, eliminating the need for users to activate a separate logon or provide profile information.
Attachment Handling, Message Response
CDO 1.2 supports file attachments in much the same way as its predecessor, Active Messaging 1.1. With CDO 1.2, developers can take a message and attach to it a file, a link to a file, an OLE object, or another message. They also can upload files using any RFC standard 1867 Web browser.
CDO 1.2 provides wide support for message response: the return of a new, unsent message object using Reply(), ReplyAll(), and Forward(). For example, by calling Reply (or ReplyAll) on a message object, developers are returned another message object, including the new recipient and the sender of the original message. Similarly, by calling Forward() on a message object, developers are returned a new message object, including attachments but excluding the name of a new recipient. This is the same functionality as you would expect from using forward and reply in the Outlook client.
For arranging meetings, CDO 1.2 provides a number of objects, methods, and properties. For example, to support the processing of meeting requests through a calendar, CDO 1.2 enables developers to create agents that “watch” for incoming meeting requests and automatically process them. CDO 1.2 also supports applications that use the normal Exchange mechanism of reminders to set up and process meeting requests.
CDO 1.2 distinguishes between appointments and meetings. For example, inside a calendar store are objects known as AppointmentItems, which are used for creating new appointments. When an AppointmentItem has recipients added to it, it changes into what’s known as a MeetingItem and appears in a user’s inbox as a request to
Microsoft Exchange Introduction to Collaboration Data Objects White Paper3