Microsoft JScript runtime error: menuLayer is null or not an object

The error means that the object is NULL. Why it is NULL it is difficult to predict as I don't have any information from you

  <a href="#" name="link5" id="link5" onmouseover="MM_showMenu(window.mm_menu_0113121343_0,0,25,null,'link5')"
                onmouseout="MM_startTimeout();">Communication </a>

 window.mm_menu_0113121643_0 = new Menu("root", 200, 22, "Arial, Helvetica, sans-serif", 11, "#000000", "#FFFFFF", "#E4E3E3", "#787878", "left", "middle", 3, 0, 1000, -5, 7, true, false, true, 0, false, false);       
            mm_menu_0113121643_0.addMenuItem("Leave&nbsp;App", "location='leave.aspx'"); 
            mm_menu_0113121643_0.addMenuItem("Email", "location='Email.aspx'");           
            mm_menu_0113121643_0.hideOnMouseOut = true;
            mm_menu_0113121643_0.bgColor = '#555555';

same for other links with the

0113121643_0 changed to 45 works

You need to contact the script owner from where you have taken the script as internally I have no idea what it is and how it works

ok