Last modified: July 23, 2011
Applies to: Outlook
Describes a named property.
The MAPINAMEID structure is used to describe named properties properties that have identifiers over 0x8000. A property set is an important part a named property. For example PS_PUBLIC_STRINGS or PS_ROUTING_ADDRTYPE are property sets defined by MAPI.
Named properties enable clients to define custom properties in a larger namespace than is available in the MAPI-defined property identifier range. Property names cannot be used to obtain property values directly; they must first be mapped to property identifiers through the IMAPIProp::GetIDsFromNames method. For particular objects such as messages, MAPI reserves a range of property identifiers for custom properties. Therefore, for these objects, clients do not have to use named properties and can save the associated overhead.
For more information about named properties, see Named Properties.