Posted by Alec on Mon, 02 Mar 2009, in Telerik Tools
Sometimes, somehow Telerik controls might suddenly not appear in Visual Studio's toolbox. A quick solution would be mouse hover to toolbox, add a new tab, and then choose items. Then point to the Telerik bin file (Telerik.Web.UI) and that should populate all controls into the toolbox.
http://www.telerik.com/community/forums/aspnet-ajax/general-discussions/radcontrols-not-appearing-in-toolbox.aspx