You might need to wait a little longer to let the Successful mesage box to appear, say maybe 5 to 10 minutes.
If the message box still cannot appear after the burning is completed, and you see the burner has stopped burning (the most obvious symptom is the burning light on the burner panel is not flashing anymore), just right click on Windows Task Bar to invoke the Task Manager, then search for BurnNow.exe and terminate its process.
If this still cannot fix the problem, follow the instructions in
http://www.ulead.com/tech/suppform.htm to fill the tech support form to let Ulead know the situation and ask for help. Before filling the form, you need to register yourself as a Ulead member. Please use an non-free e-mail account in the Ulead member registration process and make sure the spam filter in your e-mail program or ISP has removed
support@ulead.com from the spam list so you can get the auto-reply mail from Ulead.
Hope this helps.
H.T.