Loading Toolbox content from package takes a very long time in Visual Studio .NET

Developers report situations where the Loading Toolbox Content message appears on the Visual Studio taskbar at startup and takes a very long time to load. Here is a workaround, courtesy of Microsoft Connect:

1.Exit Visual Studio
2.Navigate to your user profile directory for Visual Studio (this is found at %USERPROFILE%\AppData\Local\Microsoft\VisualStudio\10.0)
3. Make sure you have enabled "Show Hidden Files and Folders" in the Explorer Tools/Folder Options/ View pane.
4.Delete the TBD files found there (they are usually hidden files)
5.Re-start Visual Studio and open your solution - the toolbox will be initialized