Use C++ code and make hacks

#include <windows.h>

BOOL WINAPI DllMain ( HMODULE hDll, DWORD dwReason, LPVOID lpReserved )
// DllMain is an optional function for you to declare.
// It serves as the entry point for any DLL
{
	DisableThreadLibraryCalls(hDll);
	// Make a call to DisableThreadLibraryCalls with the hModule variable
	// as its argument; Doing this is an optimization trick to prevent
	// needless thread attach/detach messages from triggering further calls
	// to our DllMain function.
	if ( dwReason == DLL_PROCESS_ATTACH )
	{
		//When your process gets attached, show a messagebo.
		MessageBoxA(NULL, "This is my MsgBox WOO :D", "My MsgBox", MB_OK);
		//The message will say "This is my MsgBox WOO :D" with the title of "My MsgBox".
		//The only button that the messagebox will be the OK button.
	}
return TRUE;
// Although the return value doesn't actually matter. You return the value TRUE or FALSE indicatinng success or failure.

}