I have found a strange problem that I need help with.

After previewing labels in a maximized window, I close the preview window, then the form. When any menu on my
application drops down, I cannot select any task. When a task is highlighted, if I click on it, it will not execute. I have
to shut down my application and restart it.

This does not happen when I keep the preview window in minimized mode.

Thanks for any suggestions.