Whilst hosting ASP .NET site, you may come stumble upon the following error:

Server Error in '/' Application.
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'~/Telerik.Web.UI.WebResource.axd' is missing in web.config. RadScriptManager requires a HttpHandler registration in web.config. Please, use the control Smart Tag to add the handler automatically, or see the help for more information: Controls > RadScriptManager
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.InvalidOperationException: '~/Telerik.Web.UI.WebResource.axd' is missing in web.config. RadScriptManager requires a HttpHandler registration in web.config. Please, use the control Smart Tag to add the handler automatically, or see the help for more information: Controls > RadScriptManager
To resolve the above issue, you would need to make the following entry in your web.config file for the site:

Code:
<system.webServer>

<handlers>

 <add name="Telerik.Web.UI.WebResource"  path="Telerik.Web.UI.WebResource.axd" verb="*" type="Telerik.Web.UI.WebResource, Telerik.Web.UI" />

</handlers>
</system.webServer>
Now save the web.config file, restart the site from IIS Manager and browse the site, the error will disappear

Please also make sure that ASP .Net 4.0 has been assigned to your website.


KelvinS