Sylvain,
I created 3 forms, A, B, C. A is modal, B is modal, C is modeless. I put 2 buttons on A to launch the other 2 forms with a simple DO FORM FORMB and DO FORM FORMC
All the forms launch just fine. FormC is effectively modal though because it's launched from a modal form. You can't launch C, then try and click back to A to also launch the B form.
>No, there are not part of a formset and no, I do not use LockScreen.
>
>Form A is modal by the way, so that may be my problem. I would try to put it modeless and run the form again to see if it run OK.