Upgrade from 2009 to 2011 Causing Issues

[Stephen Wright]

I upgraded our ASP.NET AJAX controls from version 2009.3.1314.35 to 2011.1.519.35.  A customer still uses a Windows 2000 machine with IE6 (6.0.2600) installed. They are unable to use our site due to a javascript error:

'Sys.Application' is null or not an object

This does not occur on their machines with Windows XP with IE6, nor does it occur on the site when using the previous version installed (2009.3)

Any direction on what might be causing this would be helpful. 

EDIT: Further investigation shows that the Telerik.Web.UI.WebResource.axd is being loaded BEFORE the ASP.NET AJAX ScriptResource.axd when the page errors.  Why would this happen?

[Stephen Wright]

This was the issue:

http://support.microsoft.com/default.aspx?scid=kb;en-us;Q312496 

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