>Hi
>
>I am trying to colse an application using the above api functions, but I always get a return value of zero, can you tel me what I am doing wrong
>
>lnOk=PostMessage (thisform.lnActiveWindowHandel, WM_CLOSE, 0, 0)
>

A few questions - what is in lnActiveWindowHandle (ie are you sure it's a valid handle?)

What do you have defined as WM_CLOSE (are you sure the value is defined properly?)

What is the error returned by GetLastError()?

You should probably read the MSDN Library documentation on PostMessage() if you aren't sure of the answers; the information you give is inadequate to analyze the error.