Eris many thanks, it's works.
I've created a new form from scratch and it works.
Now, this make me answer another question: I've noticed that sometimes "playing" with the form can cause code doesn't execute.
I mean, for example: drop a button, insert some code for the click event, then move the button in a panel, or in tabcontrol, the code for the click event is there, but doesn't fire.
Should this happens, or am I wrong?
Thanks