Type is undefined (javascript) when update. (F5)

I have a mayor problem, when the client clicks F5 in IE, I get Type is undefined from my webserviceses (the Type from MicrosoftAjax.js)
Type.registerNamespace('MyNameSpace'); <-- Type is undefined Also in FF i randomly gets the same error... RANDOMLY there is no other javascript error, there is no other Type declared.We are about to release this new mayor big newspapersite in sweden with AJAX.NET and its not working 100%. Please help.Here is the top of html: 1 <HTML><HEAD><title> 2 the title here 3 </title> 4 <LINK href="/favicon.ico" type=image/x-icon rel="shortcut icon"&g ...