There is a rare case when some files remain from the previous installations and thus breaking the VSExtensions. I guess you might have experienced that exact problem. Could you please try the following steps in order to reinstall the Extensions?
- Close all Visual Studio instances
- Use Windows Explorer to check the following two folders for "Telerik [ProductName] VSExtensions" subfolder and delete it if if exists:
- Open VS2010 and go to Tools -> Extension Manager. Go to the Online Gallery and in the Search field in the top right corner type Telerik.
- Download and install Telerik [ProductName] VSExtension. Restart the studio if it prompts to.
- Run Visual Studio again to check if everything is fine now.
Let me know if that helps.
Wpf upgrad wizard missing fix.