>I have a top-level login form I have setted _SCREEN.VISIBLE = .F. in form's init event and revert it when OK button clicked. My problem is when I want to run my program then login form is displayed but inactive, I have to click init to active it. I tried with SCREEN = OFF but same. Any one have idea about this?

Try this code to force window activation via Windows API

DECLARE INTEGER ShowWindow IN WIN32API AS APIShowWindow  ; 
    LONG HWND, LONG nCmdShow 
DECLARE INTEGER BringWindowToTop IN WIN32API AS APIBringWindowToTop ; 
        LONG HWND 

APIShowWindow(ThisForm.HWnd, 9)
APIBringWindowToTop(ThisForm.HWnd)

CLEAR DLLS APIShowWindow  
CLEAR DLLS APIBringWindowToTop

HTH