Removing all unused references from a project in Visual Studio projects

If you have Resharper (plugin) installed, you can access a feature that allows you to analyze used references via Solution Explorer > (right click) References > Optimize References...

http://www.jetbrains.com/resharper/webhelp/Refactorings__Remove_Unused_References.html

This feature does not correctly handle:

• Dependency injected assemblies
• Dynamically loaded assemblies (Assembly.LoadFile)
• Native code assemblies loaded through interop
• ActiveX controls (COM interop)
• Other creative ways of loading assemblies

The Resharper extension will do this for you.

This extension supports Visual Studio 2005 through 2017.

While the compiler won't include unused assemblies, extraneous using statements and references slows down Visual Studio and Intellisense, since there's more code the tools have to consider.