Error Creating Control - RadScriptManager1Failed to create designer 'Telerik.Web.UI.RadScriptManager, Telerik.Web.UI, Version=2018.1.117.45, Culture=n

[gc_0620]

Folks,

Using Windows 10 with VS 2017 and Progress® Telerik® UI for ASP.NET AJAX (Version 2018.1.117.45).
Each time I download a new updates, I get attached error message.

Is taking about 2-3 days to research to find out the root cause of this error. Pretty frustrating.
I manually added Telerik.Web.UI.dll and Telerik.Web.UI.Skins.dll in Bin Folder of my project. Also copied both files into C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\Common7\IDE\PublicAssemblies folder. Still no luck.

Telerik please give us a solution what can be done. 2-3 days time is not acceptable to senior management of our organization.

Also by mistake I made the same post in general discussions. Please delete the thread from there.

Thanks
gc_0620

[Rumen]

Hi there,

The Telerik.Web.Design.dll assembly is no longer added to the GAC by the automated installer and this causes the design-time error if you upgrade via the Upgrade Wizard and your project did not have an explicit reference to the Telerik.Web.Design.dll file in the project folder. You can read more in this section of the documentation: Error Creating Control Failed To Create Designer after upgrade to R1 2018. 

You can download the hotfix archive from your Telerik.com account, so you can easily copy the Telerik.Web.Design.dll assembly to your target location.

Regards,
Rumen
Progress Telerik

[gc_0620]

Thanks Rumen, it works.

Possible in the future if any hotfix need to be downloaded for any Telerik Products, notify usl(end users) via e-mail?

This will save us some time not to search by Googling to get the answers.

Appreciate again for your quick response.

gc_0620

[Rumen]

You are welcome, gc_0620. 

Thank you for the nice idea. While it may be irritating for some customers to receive such notification emails, if there is a subscription group that may be a nice way to notify the customers about breaking changes and improvements. We will have your proposal in mind.

Best regards,
Rumen
Progress Telerik

[Rumen]

Hi,

I am following up with good news that the "Error creating control Failed to create designer" issue is already fixed in version 2018.1.215.2 of Telerik ASP.NET AJAX VSExtensions 
From the Release notes -> Telerik.Web.Design.dll is not added to the Bin folder of a newly created Telerik AJAX site/app. 

To fix the problem:

• Download the latest Telerik ASP.NET AJAX VSExtensions installation from the VS Marketplace, install it and restart your Visual Studio.
• Or wait for the next official R2 2018 release of Telerik UI for ASP.NET AJAX, to be out in May.
• The already provided solution for manual registration of the Telerik.Web.Design.dll in the Bin folder of the app is still applicable.
  
   

Regards,
Rumen
Progress Telerik