Petros,

The problem with the code is that your test is finding itself. Here's a better way to do this in your main.prg

lcCaption = "My application" && the real application window caption

_screen.Caption = lcCaption + sys(2015) && temporarily hack the caption

lnHWND = FindWindow( ... lcCaption ... )

if ( lnHWND > 0 )
   return
endif

_screen.Caption = lcCaption && set to the real caption

>I used your code in my main.prg under the command :
>
>MODIFY WINDOW SCREEN TITLE "app caption" ICON FILE XXX.ICO NOCLOSE
>
>and the lnWinHandle = 1928 the first time the i am starting the .exe