Can't load custom DLL - c++

Question

I created a simple DLL that open cmd.exe.
I did it with these options:
In the default dlllmain.cpp I added a code that creates a new cmd.exe:
// dllmain.cpp : Defines the entry point for the DLL application.
#include "stdafx.h"
#include <Windows.h>
BOOL APIENTRY DllMain( HMODULE hModule,
DWORD ul_reason_for_call,
LPVOID lpReserved
)
{
switch (ul_reason_for_call)
{
case DLL_PROCESS_ATTACH:
{
STARTUPINFO info = { sizeof(info) };
PROCESS_INFORMATION processInfo;
BOOL h = CreateProcessW(L"C:\\Windows\\System32\\cmd.exe", L"", NULL, NULL, TRUE, 0, NULL, NULL, &info, &processInfo);
}
case DLL_THREAD_ATTACH:
case DLL_THREAD_DETACH:
case DLL_PROCESS_DETACH:
break;
}
return TRUE;
}
These three lines below the DLL_PROCESS_ATTACH worked for me when I tested it with a console application.
I am expecting that every process that will load this DLL will open cmd.exe.
I tried to load the DLL with PowerShell:
Add-Type -TypeDefinition #"
using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
public static class Kernel32
{
[DllImport("kernel32", SetLastError=true, CharSet = CharSet.Ansi)]
public static extern IntPtr LoadLibrary(
[MarshalAs(UnmanagedType.LPStr)]string lpFileName);
}
"#
$LibHandle = [Kernel32]::LoadLibrary("C:\tmp\myDll.dll")
But nothing happens, the value of the $LibHandle was 0.
What I am doing wrong ?

Answer 1

I found what was the problem.
My system is 64 bit and the file was compiled in 32 bit.
I needed to specify in Visual Studio that I am compiling it in x64 bit.
I didn't check it in the beginning because I thought that when I am compiling it on "Any CPU" mode, it compile the file in 64 bit automatically as the OS architecture.
Now it works fine.