I

identity
A unique representation by which a service provider and its associated message service are known to a messaging system for a given session. Typically but not necessarily, the identity is supplied by an address book provider and derived from properties that identify the messaging user that initiated the session. The identity is exposed in the identity properties PR_IDENTITY_DISPLAY, PR_IDENTITY_ENTRYID, and PR_IDENTITY_SEARCH_KEY. For more information, see Primary Identity.
IID
See interface identifier.
Inbox
A folder within the interpersonal message (IPM) subtree that is designated as the default destination for incoming messages. See also IPM subtree, receive folder.
information service
See message service.
interface
A collection of related methods exposed by a given class of objects. There is normally a one-to-one correspondence between an object class and an interface, for example address book objects and the IAddrBook interface. All interfaces inherit either directly or indirectly from IUnknown. See also MAPI interface.
interface identifier
(IID) A constant that represents a particular interface and is used to request a pointer to the interface in order to call its methods. For example, the IID for the IAddrBook interface is IID_IAddrBook. Interface identifiers are defined using the IID structure, which is a specialized GUID structure.
International Telecommunications Union
(ITU) See CCITT.
interpersonal message
(IPM) A message that is sent or received by a human user rather than an application or process. Interpersonal messages have message class IPM.Note. See also IPC message, non-IPM message.
interprocess communication
(IPC) The exchange of data between two or more processes or applications. This exchange takes place solely through software, without any human intervention.
IPC message
A message that is sent and received by interprocess communication rather than by human users. See also interpersonal message, non-IPM message.
IPM
See interpersonal message.
IPM subtree
(interpersonal message subtree) An area of a folder hierarchy reserved by MAPI for interpersonal message (IPM) applications. Only information stored within the IPM subtree is visible to IPM users. Folders are commonly created to handle incoming, outgoing, sent, and deleted interpersonal messages. These, together with any other folders created for IPM usage, constitute a subtree of the message store which can be accessed through the message store's PR_IPM_SUBTREE_ENTRYID property. The default names for the common folders are the Inbox, Outbox, Sent Items folder, and Deleted Items folder.