Few days ago, I upgraded my work machine from windows XP to windows 7, one of my projects which use global theme and telerik control stopped working on my local machine. Here is the solution I've found so far to fix this error.

First solution:

Change the project's application pool under IIS 7 or IIS 7.5 to "classic mode". It will simply solve all the problems. What I think is because IIS7 & IIS 7.5 total change the pipeline.

Second solution:

Add this line '<add name="Telerik_Web_UI_WebResource_axd" path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource" verb="*" preCondition="integratedMode,runtimeVersionv2.0"/>' under <system.webServer> section.