Client applications call the IMAPIFormContainer::ResolveMessageClass method to resolve a message class to a form within a form container. The form information object returned in the ppforminfo parameter provides further access to the properties of the form with the given message class.
To resolve a message class to a form, pass in the name of the message class to be resolved (for example, IPM.HelpDesk.Software). To force the resolution to be exact (that is, to prevent resolution to a base class of the message class), the MAPIFORM_EXACTMATCH flag can be passed in the ulFlags parameter.
The class identifier for the resolved message class is returned as part of the form information object. Do not assume that the class identifier exists in the OLE library until after you call either the IMAPIFormMgr::PrepareForm or IMAPIFormMgr::CreateForm method.