I get this error using Sitecore:

'~/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

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[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] Telerik.Web.UI.RadScriptManager.OnPreRender(EventArgs e) +161 System.Web.UI.Control.PreRenderRecursiveInternal() +80 System.Web.UI.Control.PreRenderRecursiveInternal() +171 System.Web.UI.Control.PreRenderRecursiveInternal() +171 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +842

I have tried adding lines like this with the correct versions for my DLLs:
        <add verb="*" path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource, Telerik.Web.UI, Version=2010.2.826.35, Culture=neutral, PublicKeyToken=121fae78165ba3d4" validate="false" />

I have this at the moment:
<add verb="*" path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource" />

If I create a blank page and drag the control on from my toolbox I get a red message on it saying 'Error Cannot render control' so I can't get it to auto add the necessary stuff into the web.config.

This works across our sites and on my colleagues computers but not mine.

What is missing?

Hi,

These are the handlers needed for RadEditor and RadScriptManager:

<httpHandlers>
      <add path="Telerik.Web.UI.DialogHandler.aspx" type="Telerik.Web.UI.DialogHandler" verb="*" validate="false"/>
      <add path="Telerik.Web.UI.SpellCheckHandler.axd" type="Telerik.Web.UI.SpellCheckHandler" verb="*" validate="false"/>
      <add path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource" verb="*" validate="false"/>
</httpHandlers>

and

<system.webServer>
    <modules runAllManagedModulesForAllRequests="true"/>
    <validation validateIntegratedModeConfiguration="false"/>
    <handlers>
      <add name="Telerik_Web_UI_DialogHandler_aspx" verb="*" preCondition="integratedMode" path="Telerik.Web.UI.DialogHandler.aspx" type="Telerik.Web.UI.DialogHandler"/>
      <add name="Telerik_Web_UI_SpellCheckHandler_axd" verb="*" preCondition="integratedMode" path="Telerik.Web.UI.SpellCheckHandler.axd" type="Telerik.Web.UI.SpellCheckHandler"/>
      <add name="Telerik_Web_UI_WebResource_axd" verb="*" preCondition="integratedMode" path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource"/>
    </handlers>
  </system.webServer>

It is not needed to specify fully qualified names and I do not recommend you to set them to avoid versioning problems.


All the best,
Rumen
the Telerik team

I tried these with no luck - I get exactly the same error. It was pretty much what we had anyway.

Would there be anything else that would be causing this?

Still broken - any ideas!?

Hi,

You can try the following:

Add a <location> section to the application configuration file to allow access to Telerik.Web.UI.WebResource.axd to all users, like:

You can also check this forum thread on the subject: IIS7 and Telerik.Web.UI.WebResource.axd' is missing in web.config and this online resource Resolving the error: ~/Telerik.Web.UI.WebResource.axd is missing in web.config.

Regards,
Rumen
the Telerik team

Changing from integrated to classic fixed it.

Thank you so much for the help! Very much appreciated. =)

Thanks Rumen
You are Genius!!

that httpHandlers tag needs to go INSIDE of system.web in the web.config file***

Hello Daniel,

Yes, the httpHandlers should be placed in the system.web section and the handlers - in system.webServer. You can find additional information on this matter in this KB article.

Regards,
Ianko
Telerik

The problem we had was that our entire site was configured in a location node in the web.config so that child apps wouldn't get the settings.

Looks like the issue is that the registration of the handlers in the handler sections within that location node was not being detected by the script manager and it throws the error, even though they are registered.

The fix I found, that doesn't require changing to Classic pipeline, is to set the EnableHandlerDetection property to false on the RadScriptManager

I had added the httpHandlers and system.webServer handlers above, along with this <location> section in my web.config after running across this forum, but this was not enough.

I then installed the Telerik.Web.UI (2013_3_1015) and Telerik Extensions for ASPNET MVC (2013_2_611), and when I re-launched my web project in Visual Studio 2010, a Telerik notice saying my web.config's extensions were out of date asked if I wanted it to re-write the web.config to take advantage of the new extensions.  I told the wizard to do this and checked the box to copy in the referenced DLLs to the project.  I did a build, publish, and the site finally came up with no error. 

I did a "diff" on the web.config from the previous version.  It had the changes mentioned here, but quite a few more:

    -  <compliation> tag now has strict=false and explicit=true
    -  In httpHandlers, Telerik.Web.UI.WebResource.axd's type resource no longer has ", Telerik.Web.UI" in addition to "Telerik.Web.UI.WebResource" -- only the latter remains.
    -  Additional httpHandlers were added: 

    -  Additional <handlers> in <system.webServer> have been created:

And, at the end of <system.webServer>, this <modules> tag has been inserted:

There were other "remove name" tags like that in the httpHandlers and system.webServer handlers for each value, too.

So you may be able to edit your web.config manually, like above, and add that <location> piece, or install the extension tools and latest Telerik.Web.UI and have the system re-write your web.config for you.

Hopefully all of this may help someone.

super really it is very helpful thanks

Hi, I'm having the same issue in Sitecore. Where can I set EnableHandlerDetection to false?

Thanks, it workd fine by using Classic mode

I added the below code

Step1: Web.config

<httpHandlers>
      <add path="Telerik.Web.UI.DialogHandler.aspx" type="Telerik.Web.UI.DialogHandler" verb="*" validate="false" />
      <add path="Telerik.Web.UI.SpellCheckHandler.axd" type="Telerik.Web.UI.SpellCheckHandler" verb="*" validate="false" />
      <add path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource" verb="*" validate="false" />
    </httpHandlers>
  </system.web>

 

Step2: Go to IIS,

Navigate to your application under Default WebSite

And check the adtvanced setting.

Check the Application pool & Make a note of it. (ABC)

------------------------------

Navigate to Application Pool

Select the ABC and change the managePileline mode to Classic

Everything starts working perfect

 

 

 

 

Thanks.  Change to integrated worked for me too. I'm not sure why.

Hi all,

Since this is a popular forum for the Telerik handlers I'd like to share the following important articles from the documentation with you:

web.config Settings Overview
and
General Troubleshooting.

I hope that it will guide you and solve future occurring problems related to the web.config.

Regards,
Rumen
Progress Telerik