Last modified: July 23, 2011

Applies to: Outlook

Performs a task such as displaying a dialog box or starting a programmatic operation when a client application user clicks the button control.

HRESULT Activate(
  ULONG ulFlags,


[in] Reserved; must be zero.


[in] A handle to the parent window of the dialog box on which the button control appears.


The button control was successfully activated.

The IMAPIControl::Activate method performs tasks following a user's click of the button control. After the click occurs, as part of the processing of the display table, MAPI makes a call to Activate after first calling IMAPIControl::GetState to determine whether the button is enabled.

For more information about how to implement Activate and the other IMAPIControl : IUnknown methods, see Control Object Implementation.