title: Can't change text of control
body: <p>I wrote a simple winforms application which does some task every 30 seconds (using a timer). There is a function which is called each time its "time event" is raised.</p>
  
  <p>In this function I am also trying to change some text that appears in some label. I try to do it by calling <code>BeginInvoke</code> - but this does not change the text.</p>
  
  <p>Then I also try to call it by simple <code>.Text = "some Text"</code> - but this also did not work. </p>
  
  <p>How can I change the control's properties?</p>