I just installed the Telerik free trial ASP.NET AJAX controls for Visual Studio 2010 Web Express.

I added the controls to the toolbar, and I can drop controls on the forms...

Problem is:

1) It always says Telerik.web.ui.[ControlName].... is not defined:
For Example: Type 'Telerik.Web.UI.Skins.RadButton' is not defined.

2) I cannot select the skins either...

Attempts thus far:

1) Added reference to all the .DLL's directly from the project
2) I was going to add a handler to the web.config, but not sure if this is still applicable in newer versions of the controls.

Not sure what I need to do next?

Actually I'm using VS.NET 2010 Dev Express (not 2012).

Hi Kevin,

The error you are currently facing indicates that there is a mismatch between the loaded dll assemblies and the ones that the project is initially build with . Please refer to the following topics where possible solutions to this problem are described:
 http://www.telerik.com/help/aspnet-ajax/introduction-troubleshooting.html
 Design-time Troubleshooting
 http://www.telerik.com/help/aspnet-ajax/introduction-troubleshooting-skins.html
 RadControls Trial Message

Could you please share whether you have tried the Telerik Upgrade Wizard?
http://www.telerik.com/help/aspnet-ajax/introduction-vsx-upgrade-wizard.html

I hope this will prove helpful.

All the best,
Eyup
the Telerik team