function getInternetExplorerVersion()
// Returns the version of Windows Internet Explorer or a -1
// (indicating the use of another browser).
{
	var rv = -1; // Return value assumes failure.
	if (navigator.appName == 'Microsoft Internet Explorer') {
		var ua = navigator.userAgent;
		var re = new RegExp("MSIE ([0-9]{1,}[\.0-9]{0,})");
		if (re.exec(ua) != null)
			rv = parseFloat(RegExp.$1);
	}
	return rv;
}
function checkIEVersion() {
	var msg = null;
	var ver = getInternetExplorerVersion();
	if (ver > -1) {
		if (ver < 8.0) {
			msg = "You're using an older version of Internet Explorer. \nPlease upgrade your browser to get the best experience on this web site.";
			alert(msg);
		}
	}
}

function getCookie(c_name) {
	var i, x, y, ARRcookies = document.cookie.split(";");
	for (i = 0; i < ARRcookies.length; i++) {
		x = ARRcookies[i].substr(0, ARRcookies[i].indexOf("="));
		y = ARRcookies[i].substr(ARRcookies[i].indexOf("=") + 1);
		x = x.replace(/^\s+|\s+$/g, "");
		if (x == c_name) {
			return unescape(y);
		}
	}
}
function setCookie(c_name, value, exdays) {
	var exdate = new Date();
	exdate.setDate(exdate.getDate() + exdays);
	var c_value = escape(value) + ((exdays == null) ? "" : "; expires=" + exdate.toUTCString());
	document.cookie = c_name + "=" + c_value;
}

function checkCookie(c_name) {
	var cookieSet = getCookie(c_name);
	if (cookieSet != null && cookieSet != "")
		return true;
	else
		return false
}

function alertIE7Users() {
	var hasBeenAlerted = checkCookie("isIEVersion");
	//alert(' hasBeenAlerted ' + hasBeenAlerted);
	if (!hasBeenAlerted) {
		checkIEVersion();
		setCookie("isIEVersion", "1", 7);
	}
}

alertIE7Users();