PidLidTaskOrdinal Canonical Property

Applies to: Outlook 2013 | Outlook 2016

Provides an aid to custom sorting tasks.

Associated properties:
Property set:
Long ID (LID):
Data type:


This property may be left unset. If set, its value must be greater than "0x800186A0" (-2,147,383,648) and less than "0x7FFE7960" (2,147,383,648) and must be unique among tasks in the same folder.

Whenever the client sets this property to a number less than the negative of the current value of the PR_ORDINAL_MOST (PidTagOrdinalMost) property of the folder, the client must also update PR_ORDINAL_MOST on the folder.

The PR_ORDINAL_MOST property of the folder provides an efficient way to determine a unique value among tasks in the same folder.

Protocol specifications


Provides property set definitions and references to related Exchange Server protocol specifications.


Defines several objects that model the electronic equivalent of tasks, task assignments, and task updates.

Header files


Provides data type definitions.

See also

MAPI Properties

MAPI Canonical Properties

Mapping Canonical Property Names to MAPI Names

Mapping MAPI Names to Canonical Property Names