How to: Display a Control in the Customize Toolbox Dialog Box
As you develop and distribute controls, you may want those controls to appear in the Customize Toolbox dialog box, which is displayed when you customize the Toolbox. You can enable your control to appear in this dialog box by either setting the appropriate registry key value or by installing your control to the Global Assembly Cache.
To display your control in the Customize Toolbox dialog box
Install your control assembly to the Global Assembly Cache. For additional information, see How to: Install an Assembly into the Global Assembly Cache
Use the Windows utility Regedit.exe to create a registry key at HKEY_LOCAL_MACHINE\Software\Microsoft\.NETFramework\v2.0.x\AssemblyFoldersEx\Public Assemblies\<KeyName> and set the Default string value to the file location where your assembly is found. <KeyName> can be any value you prefer.
In Visual Studio .NET 2003, this key should be created at HKEY_LOCAL_MACHINE\Software\Microsoft\Visual Studio\7.1\AssemblyFolders\<KeyName>. In Visual Studio .NET 2002, this key should be created at HKEY_LOCAL_MACHINE\Software\Microsoft\.NET\AssemblyFolders\<KeyName>.