Compiler Error CS0423

Since 'class' has the ComImport attribute, 'method' must be extern or abstract

Specifying the ComImport attribute implies that the implementation for the class is to be imported from a COM module. Additional methods may not be defined.

The following sample generates CS0423:

// CS0423.cs  
using System.Runtime.InteropServices;  
class ImageProperties  
  public static void Main()  // CS0423  
    ImageProperties i = new ImageProperties();