var an=navigator.appName;
var ua=navigator.userAgent;

if ((an == "Microsoft Internet Explorer") || (ua.indexOf("MSIE") > -1) || (typeof( navigator.appMinorVersion ) != "undefined")){ 
	//MSIE
}else if(ua.match(/Opera[\/\s](\d\.\d+)/)){
	//Opera
}else if(ua.match(/Chrome\/([\.\d]+)/)){
	//Google Chrome
}else if(ua.match(/Safari\/([\.\d]+)/)){
	//Safari
}else if(ua.match(/Gecko/)){
	if(ua.match(/Firefox\/([\.\d]+)/)){
		//Firefox
	}else{
		location.href = "error.html";
	}
}else{
	if(navigator.appVersion.charAt(0) < "4"){
		location.href = "error.html";
	}
	
	if(ua.indexOf("OPERA") >= 0){
		location.href = "error.html";
	}
	
	for(var i=0; i<navigator.plugins.length; i++){
		if( (navigator.plugins[i].name.toLowerCase()).indexOf("opera")>-1 )location.href = "error.html";
	} 	
}