The following steps produce a problem in my App:

I run my .EXE file
I execute a menu item (a report) using the preview option.
I maximize the window
I close this window.

After these steps, i can navigate the main menu but i can't execute any menu item again.

Note: If i don't maximize the window, there is no problem.

Does anyone know this problem?
How can i solve it?

Thanks.

Juan Carlos