System.DllNotFoundException in C# when use a native C++ dll

Question

Hi everyone

I have a native C++ dll. Its closed source. I want to use it in my C# app, So I have to wrap the main dll with a class in C++. and I use this new wrapper dll in my C# app. please attention:

++) The main dll (that is closed source) called Engine.dll include the [int Init(UINT32 flag)] method.

I builed a C++ dll called DllWrapper.dll that use the above method, like bellow:

extern "C"

{

               __declspec(dllexport) int Init(UINT32 flag, int *result)

               {

                           // use the APIs of the Engine.dll

               }

}

And in my C# app I use this dll. So in my machine (dev machine) the app is fine work. But when I copy the app and all required dll (all path is correct) in other machines and when I run the app, the following exception raised:

System.DllNotFoundException: Unable to load DLL "DllWrapper.dll": The specified module could not be found. (Exception from HRESULT: 0x8007007E)

 

p/s: I use the VS 2013 IDE.

Can any one help me?

Thanks in advanced.