| Attachment | Represents an attachment to a message. |
| ExtendedProperty | Class ExtendedProperty. |
| ExtendedPropertyId | Class ExtendedPropertyId. |
| ExtendedPropertyList | Class ExtendedPropertyList. |
| ExtendedPropertyName | Class ExtendedPropertyName. |
| ExtendedPropertyTag | Class ExtendedPropertyTag. |
| Message | Represents Outlook message file. |
| Recipient | Represents a user or resource, generally a mail message addressee. |
| RecurrencePattern | Class RecurrencePattern. |
| StandardPropertySet | Class StandardPropertySet. |
| AttachmentFlags | Represents attachment's flags. |
| AttachmentMethod | Represents the way the contents of an attachment can be accessed. |
| BusyStatus | Specifies whether the attendee is busy at the time of an appointment on their calendar. The specified status appears in the free/busy view of the calendar. |
| CalendarType | Enum CalendarType |
| DayOfWeek | |
| DayOfWeekIndex | Describes which week in a month is used in a relative recurrence pattern. |
| DisplayType | Contains a value used to associate an icon with a particular row of a table. |
| FlagIcon | Represents flag color. |
| FlagStatus | Contains the Microsoft Office Outlook follow-up flags for the message. |
| Gender | Enum Gender |
| Importance | Indicates the message sender's opinion of the importance of a message. |
| LastVerbExecuted | Represents last action on the message. |
| MeetingStatus | The MeetingStatus enum specifies the status of an appointment or meeting. |
| MessageFlag | Contains a value that indicates the origin and current state of a message. |
| NoteColor | Represents Note item background color. |
| ObjectType | Represents type of an object. |
| Priority | Represents the relative priority of a message. |
| PropertyType | Enum PropertyType |
| RecipientType | Represents the recipient type for a message recipient. |
| RecurrenceEndType | |
| RecurrencePatternFrequency | |
| RecurrencePatternType | Enum RecurrencePatternType |
| RecurrenceType | Specifies the recurrence pattern type. |
| ResponseStatus | Indicates the response to a meeting request. |
| SelectedMailingAddress | Indicating the type of the mailing address for the contact. |
| Sensitivity | Identifies the sensitivity level assigned to a message item. These levels are arbitrarily set and filtered for, by the user. |
| StoreSupportMask | Contains a value that client applications should query to determine the characteristics of a message store. |
| TaskDelegationState | Represents the status types of a delegated task. |
| TaskOwnership | Indicates the ownership state of the task. |
| TaskStatus | Identifies the status types of a task item. |