About Named Properties Used by Outlook

Applies to: Office 2010 | Outlook 2010 | Visual Studio

MAPI provides a facility for assigning names to certain properties, for mapping these names to unique identifiers, and for making this name-to-identifier mapping persistent across sessions. Named properties are identified by a name and a globally unique identifier (GUID) for a property set. The name can be a number or a string. For Microsoft Outlook 2010, the property set is often a namespace defined by Outlook 2010, such as PSETID_Appointment.

Named properties are manipulated by using the IMAPIProp::GetIDsFromNames function and the IMAPIProp::GetNamesFromIDs function. The name and the property set GUID are passed to the IMAPIProp::GetIDsFromNames function to obtain a property identifier that is valid for the current MAPI session. Because this property identifier can vary from computer to computer, the only consistent way to access a named property is to know its name and property set GUID. The range for identifiers is always in the 0x8000 and 0xFFFE range.

Any object that implements the IMAPIProp : IUnknown interface can support named properties. Specifically, a MAPI service provider or a MAPI client must implement IMAPIProp::GetProps to get values of named properties. Setting named properties used by Outlook 2010 is not supported because of the risk of corrupting data that is shared with other MAPI providers or clients.

Outlook 2010 uses MAPI named properties to implement many of its features, for example, attachment security and meeting counter-proposals. Above this underlying data, Outlook 2010 exposes some of these properties as item properties in the Outlook 2010 object model. For example, the Email1Address property of the ContactItem object in the object model corresponds to the named PidLidEmail1EmailAddress Canonical Property in the PSETID_Address namespace. But in general, due to concerns for compatibility and data integrity, many of the MAPI properties that are used by Outlook 2010 are not exposed in the object model.

This reference describes a number of named properties that are listed below.

Named properties in the PSETID_Address namespace are the following:

Named properties in the PSETID_Appointment namespace are the following:

Named properties in the PSETID_Common namespace are the following:

Named properties in the PSETID_Meeting namespace are the following:

Named properties in the PSETID_Task namespace are the following:

Named properties in the PS_INTERNET_HEADERS namespace are the following:

Named properties in the PSETID_Log namespace are the following:

Named properties in the PS_PUBLIC_STRINGS namespace are the following:

See Also

Concepts

MAPI Constants

How to: Determine if Outlook Downloaded Only the Header of a Message

How to: Get the E-mail Address of a Contact Item

How to: Remove Custom Form Definition Saved With a Message