MessageBox on worker thread
<p>My application has a worker thread doing some files synchronisation.</p>

<p>Under certain condition during the sync process, my worker thread needs to make a decision to continue or not.  Hence, I think I would ask for user feedback by showing a dialog box/message box.. (Yes/No).  Which would cause the worker to either continue or stop.</p>

<p>Now the question is:<br>
Is it safe to show message box on non UI thread?<br>
Would it possibly cause any potential issues?</p>
