title: How to fix javascript pop-up "Window popup is already registered in the DOM!"?
body: <p>I am having problem on my window pop-up always says:
  "Window popup is already registered in the DOM! Make sure you use setDestroyOnClose() or destroyOnClose: true in the constructor"</p>
  
  <p>I already read other forums but I haven't find a solution on my problem.</p>
  
  <pre><code> &lt;script&gt;   
       var win1 = null;
                  function openPopupProduct(width,height,image1, image2, image3,image4, header) {
                      if(win1==null){
                          win1 = new Window('popup', {className: "alphacube", maximizable:false, minimizable:false, showEffectOptions: {duration:0.2}, hideEffectOptions: {duration:0.2} } ); 
                          }
                          width = width+150;
                          height = height+150;
                          newHTML = '&lt;div class="noborder_preview" style="width:'+  width +'px;height:'+ height +'px"&gt;';
                          newHTML = newHTML + '&lt;div class="preview_temp_load"&gt;';
                          newHTML = newHTML + header + '&lt;br /&gt;';
                          newHTML = newHTML + '&lt;img src="' + image1 + '" border="0"&gt;';
  
                          if(image2 != '') {
                              newHTML = newHTML + '&amp;nbsp;&lt;img src="' + image2 + '" border="0"&gt;';
                          }
  
                          if(image3 != '') {
                              newHTML = newHTML + '&amp;nbsp;&lt;img src="' + image3 + '" border="0"&gt;';
                          }
  
                          if(image4 != '') {
                              newHTML = newHTML + '&amp;nbsp;&lt;img src="' + image4 + '" border="0"&gt;';
                          }
  
                          newHTML = newHTML + '&lt;\/div&gt;';
                          newHTML = newHTML + '&lt;\/div&gt;';
                          win1.getContent().update(newHTML);
                          win1.setSize(width,height);
                          win1.showCenter();
                  }
      &lt;/script&gt; 
  </code></pre>
  
  <p>I hope some one can help me on this.</p>
  
  <p>Thank you in advnace.</p>