var popWindowWidth = '425'; // pop up window width (in pixels) .
var popWindowHeight = '410'; // pop up window height (in pixels).
var centerPopUpWindow = 'yes'; // do you want the pop up window to be automatically centered in browser window? yes or no. NOTE: Height is somewhat higher than center due to toolbars and browser top height.
var popWindowBackgroundColor = ''; // pop up window background color (named or rgb).
var popWindowPadding = '0'; // padding or margin between contents of pop up window and edges of pop up window in pixels.
var popWindowPositionTop = '0'; // where top edge of popup window will be displayed (ignored if centerPopUpWindow = true - see above).
var popWindowPositionLeft = '0'; // where left edge of popup window will be displayed (ignored if centerPopUpWindow = true - see above).
var popWindowBorderStyle = 'solid'; // type of border for popup (solid,double,grooved,ridged,inset,outset).
var popWindowBorderWidth = '2'; // border thickness of popup window (must be at least 3 for double style).
var popWindowBorderColor = 'black'; // color of border (named or rgb).
var popWinFontFamily = 'arial,verdana,sans-serif'; //font-family of text within pop up window. NOTE: Leave empty ('') if defined elsewhere.
var popWinFontSize = '8px'; // size of font for text in pop up window. Again, leave empty ('') if defined elsewhere.
var popWindowDelay = '0'; // microseconds before pop up is displayed (1000 = 1 second).
var popWindowShadowColor = 'black'; //drop shadow color, named or rgb - shows in IE5+ only. 'none'=no shadow.

function validateCheckoutFields () {
	var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
	if(!document.getElementById("Email").value.match(reg)) {
		alert("Please enter a valid email address.");
		return false;
	} else {
		return true;
	}
}


<!-- DO NOT CHANGE ANYTHING BELOW HERE! -->
var ie=document.all
var ns6=document.getElementById && !document.all
function showPopUp(){
    document.getElementById('pWinConfg').style.visibility='visible';
}
function hidePopUp(){
    document.getElementById('pWinConfg').style.visibility='hidden';
}   
function startPopUp(){
    timerID=setTimeout('showPopUp()',popWindowDelay);
} 
/*
	heres where we set the popup window class properties..
*/
var pWinConfg = "<style>.pWinConfg{\n";
	if(popWinFontFamily !== ''){
		pWinConfg += "font-family:"+popWinFontFamily+";\n";
	}
	if(popWinFontSize !== ''){
		pWinConfg += "font-size:"+popWinFontSize+";\n";
	}
pWinConfg += "position:absolute;\n";
pWinConfg += "width:"+popWindowWidth+";\n";
pWinConfg += "height:"+popWindowHeight+";\n";
pWinConfg += "background-color:"+popWindowBackgroundColor+";\n";
		if(centerPopUpWindow.toLowerCase() == 'yes'){
			var popTop = (screen.height/4.667) - (popWindowHeight/2);
			var popLeft = (screen.width/2) - (popWindowWidth/2);
			pWinConfg += "top:"+popTop+";\n";
			pWinConfg += "left:"+popLeft+";\n";
		}else{
			pWinConfg += "top:"+popWindowPositionTop+";\n";
			pWinConfg += "left:"+popWindowPositionLeft+";\n";
		}
pWinConfg += "border-style:"+popWindowBorderStyle+";\n";
pWinConfg += "border-width:"+popWindowBorderWidth+";\n";
pWinConfg += "border-color:"+popWindowBorderColor+";\n";
pWinConfg += "padding:"+popWindowPadding+";\n";
pWinConfg += "visibility:hidden;\n";
if(popWindowShadowColor != 'none'){
pWinConfg += "@filter: progid:DXImageTransform.Microsoft.Shadow(color="+popWindowShadowColor+",direction=135);\n";
}
pWinConfg += "}<\/style>\n";
document.write(pWinConfg);