This rule detects classes that are not public and not used. These classes are redundant as they cannot be accessed from outside the project.

These classes should either be used where appropriate or removed.

In this example the "Person" class is private so it can only be used in the class it is nested in but it is never used.
  • MSDN, Code Analysis for Managed Code, CA1812: Avoid uninstantiated internal classes.
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