>Hi Ed
>
>I get the error when the sendmessage method is being called, I have a feeling it might be the
>#define WM_CLOSE 0x0010
>
>Is this the correct way to define a message constant ?
>

That should work fine (it's a valid numeric expression); if it's complaining about too many arguments to the SendMesage invocation, I'd look at the DECLARE...DLL for SendMessage to see if a parameter definition was omitted.