Reverse engineering related small work

I have a dll which I use in my program. Whenever, it is used a form is displayed and only once saying; [Unregistered ... Plugin Please register .............................Thank you] If I close the form by clicking 'X', my program runs as normal but until I close it, program is paused. I used a resource editor and I emptied the form and it worked. But I want someone to delete the line that shows the startup form.