Try adding the assembly to the GAC of your local machine. Please note that this issue is not specific to
Telerik RadControls. You can find more useful information on the following articles to check how you can access .NET projects to be run from a shared location such as a Network drive.
Storing VS projects on a Network drive
How Do I Allow my Visual Studio .NET Projects to Run from a Network Location?
Projects on a network drive
If RadControls for ASP.NET AJAX does not appear in the Visual Studio Toolbox the main reason behind this is the Visual Studio Extensions feature of the RadControls for ASP.NET AJAX installer was not installed.
The recommended solution is to uninstall RadControls for ASP.NET AJAX (If installed) and run the installer again. Click the "
button in the Setup Type screen and ensure the "
Visual Studio Extensions for Visual Studio xxxx"
feature is selected for install where xxxx can be the version such as Visual Studio 2010 etc. Another possible reason can be Custom/third-party/Telerik exe-installer were used to register RadControls to
the toolbox, that prevent the ToolboxControlInstaller package of the
IDE to run correctly.