Originally Posted by macu

The code looks fine to me, you're making doubly sure that the thread has been stopped. If you want to check you could go to Control Panel, Admin Tools, Performance. Add a new counter and choose Process, Thread Count and your project. When you run your project you'll see your thread pool thread count, when you click start this will go up by one as you've started a new thread and when you click exit you should see it go back down to where it was before you ran the app. Another test you could do is to write the current time to a file or something in your function and you'll see this stops when you exit.