Code Inspection: Redundant using directive

tip

You can suppress this inspection to ignore specific issues, change its severity level to make the issues less or more noticeable, or disable it altogether.

Extraneous using references are a very common thing. Whenever you create, say, a WinForms window, Visual Studio preemptively adds a large number of using references in your code file. Since ReSharper is able to determine which using references are actually needed and which are redundant, it offers a warning, offering the option to remove the unnecessary references.