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UlAddRef

Last modified: July 23, 2011

Applies to: Outlook

Provides an alternative way to invoke the OLE method IUnknown::AddRef.

Header file:

Mapidefs.h

Implemented by:

MAPI

Called by:

Client applications and service providers

ULONG UlAddRef(
  LPVOID punk
);

punk

[in] Pointer to an interface derived from the IUnknown interface, in other words any MAPI interface.

S_OK

The call succeeded and has returned the expected value or values.

MAPI_E_CALL_FAILED

An error of unexpected or unknown origin prevented the operation from completing.

UlAddRef returns the value returned by the IUnknown::AddRef method, which is the new value of the reference count for the interface. The value is nonzero.

For more information about IUnknown::AddRef, see Implementing the IUnknown Interface.

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