HDExtLib is an n-tier design, client-side COM component of the HelpDesk sample application. The Administrative Explorer is the only application that uses this component. This component contains several methods that reside in the same layer as the HDClient component, but are not related to user or technician tasks. This separation was made to maintain the thinness of the HDClient and HDServer components. The Explorer uses this component to communicate with HDServer, which communicates directly to the database executive, DBExec. (The object model diagram does not show HDExtLib.)
The HDExtLib component contains the CHDExt class.