I need to write a C# application that uses unmanaged C++ code. I created a
C++/CLI wrapper to C++ code and encountered the following problem. Any time I
try to instantiate a wrapper in C# application the program crashes with an
error
"An unhandled exception of type 'System.IO.FileNotFoundException' occurred
in mscorlib.dll, Additional information: The specified module could not be
found. (Exception from HRESULT: 0x8007007E)". C# application has a reference
only to the wrapper and the wrapper has a reference to unmanaged dll. Similar
application written in C++/CLI gives exactly the same error if it has a
reference only to the wrapper namespace. In case of C++/CLI application,
VS2005 allows to add a reference to unmanaged dll and then the application
works OK.
I have seen an example of managed C++ wrapper that is virtual identical to
the code below and is claimed to work with C#
(http://www.ondotnet.com/lpt/a/4731)
Cannot figure out what is the problem with my code.
Here is the code

//CppLib.h
#ifndef _CPPLIB_EXPORT_IMPORT
    #ifdef _CPPLIB_EXPORT
       #define _CPPLIB_EXPORT_IMPORT  __declspec(dllexport)
   #else
       #define _CPPLIB_EXPORT_IMPORT  __declspec(dllimport)
   #endif
#endif

class _CPPLIB_EXPORT_IMPORT CCppLib
{
   double _a;
   double _b;
   double _c;

   public:
       CCppLib(double a, double b, double c);
       ~CCppLib(){};

   bool IsValid();

};
//CppLib.cpp

CCppLib::CCppLib(double a, double b, double c)
{
   _a = a;
   _b = b;
   _c = c;
}

bool CCppLib::IsValid()
{
   return (_a + _b > _c && _a + _c > _b && _b + _c > _a );
}

//CLRWrapper.h

#pragma once
#include "..\\CppLib\\CppLib.h"

using namespace System;

namespace CLRWrapper
{

    public ref class Triangle
    {
        CCppLib* _CppLib;

   public:

       Triangle()
       {
           _CppLib = new CCppLib();
       }

       Triangle(double a, double b, double c)
       {
           _CppLib = new CCppLib(a, b, c);
       }

       ~Triangle()
       {
         this->!Triangle();
       }

       !Triangle()
       {
           if (_CppLib != NULL)
           delete _CppLib;
           _CppLib = 0;
       }

       CCppLib* GetCppLib() { return _CppLib;}
       
       bool IsValid()
       {
           if (_CppLib != NULL)
               return _CppLib->IsValid();
           return false;
       }

    };
}

// CLRTest.cpp  C++/CLI test application
using namespace System;
using namespace CLRWrapper;

int main(array<System::String ^> ^args)
{
    Triangle^ tr = gcnew Triangle(1, 2, 3);
   Console::WriteLine(tr->IsValid());

   return 0;
}

//Program.cs C# test application

using System;
using System.Collections.Generic;
using System.Text;
using CLRWrapper;

namespace TestTriangle
{
   class Program
   {
       static void Main(string[] args)
       {
           Triangle tr = new Triangle(0.1, 0.2, 0.3);
           Console.WriteLine(tr.IsValid());
       }
   }
}