>Hello again
>
>Sorry for your time.
>
>I make a very simple example in a test project with a main.prg with the following code :
>
>
>_Screen.Caption = "xxx"
>Local lnWinHandle
>Declare Integer FindWindow In Win32API Integer, String
>
>lnWinHandle = FindWindow(0, "xxx")
>=Messagebox(str(lnWinhandle))
>If lnWinHandle <> 0
> =Messagebox( "You already Started application", 16 )
> Cancel
>Endif
>
>=Messagebox( "You are in the applicatrion")
>
>
>
>It always return me lnWinHandle > 0
>
>Thanks again
>Petros

Petros,

Try setting this instances screen caption after the check as you are looking for another existing screen with that title.

I think that currently you are getting the handle to the window you are just starting.

HTH