To safeguard Visual Studio from untested applications that might change it, the Visual Studio SDK provides an alternative build of Visual Studio that you can use to experiment. You develop new applications by using Visual Studio as usual, but you run them by using this experimental build.
The experimental build is just Visual Studio, but with another registry hive that is named the experimental hive.
To start Visual Studio by using the experimental registry hive, run the following command at the command prompt in the Visual Studio Command window:
<Visual studio installation path>\Common7\IDE\devenv.exe" /RootSuffix Exp /ranu
In Visual Studio Shell the experimental hive is written under HKEY_CURRENT_USER rather than under HKEY_LOCAL_MACHINE. You must add the /ranu switch whenever you use the /RootSuffix Exp switch.
We recommend that you register your VSPackage under the experimental hive while you are developing it. When you deploy the VSPackage, register it under the regular hive. For more information about registering applications, see Registering VSPackages.
Updating the Experimental Registry Hive
When the Visual Studio SDK is installed, it clones the existing Visual Studio registry hive. The clone becomes the experimental hive. After installation, the regular hive may change because of other installations or changes in settings. You can remove the experimental hive or reset it to the same state as the regular hive using the VsRegEx utility. For more information, see VsRegEx Command-Line Utility.