This exception indicates that the file specified in a DLL import could not be found (see System.Runtime.InteropServices.DllImportAttribute ). This exception is thrown only when you attempt to link against a method declared using the P/Invoke features of .NET. Any managed DLL (such as those produced by C# or Visual Basic .NET) that cannot be found instead generates TypeLoadException s when you attempt to resolve types out of an assembly that cannot be found. public class DllNotFoundException : TypeLoadException { // Public Constructors public DllNotFoundException ( ); public DllNotFoundException (string message ); public DllNotFoundException (string message , Exception inner ); // Protected Constructors protected DllNotFoundException (System.Runtime.Serialization.SerializationInfo info , System.Runtime.Serialization.StreamingContext context ); } HierarchyObject Exception(System.Runtime.Serialization.ISerializable) SystemException TypeLoadException DllNotFoundException |