While migrating our application to the new .NET CLR (2.0) I noticed that in addition to the .exe file an additional file was created under the same folder with the name .vshost.exe.

Doing some research to learn more about this new “.exe buddy”, I find out that this is a new feature that was introduced with the new VS to improve some debugging performance issues and added several other features such as partial trust debugging and design-time expression evaluation.

To read move about those new features, visit MSDN website.