>I just noticed one thing the problem i am facing is only happening with one form
>i call this form in main.prg except that i dont think i've any specific settings for this form.

Is this the form you want to close before you call a new form? And do call the new form from within the form you want to close?
If yes, then try to issue this code from the form you want to close..

thisform.visible = .F.
thisform.windowtype = 0
thisform.release

If still cant, try to share your code from your main.prg calling the form here in UT...