This is my Game.cpp file:

#include "Game.h"

bool quit = false;

// Starts the game
void Game::Start() {

	if ( Game::Init() == 1 ) {
			std::cout << SDL_GetError();
			quit = true;
		}
	
	while( !quit ) {
		if ( Game::Update() == 1 ) {
			std::cout << SDL_GetError();
			quit = true;
		}

		if ( Game::Draw() == 1 ) {
			std::cout << SDL_GetError();
			quit = true;
		}
	}

	SDL_Quit();
}

int Game::Init() {
	SDL_Init( SDL_INIT_EVERYTHING );

	return 0;
}

int Game::Update() {

	while (SDL_PollEvent( &event ) ) {
		if ( event.type == SDL_QUIT ) {
			quit = true;
		}
	}

	return 0;
}

int Game::Draw() {

	return 0;
}

Game::Start(); is called from main.cpp, but it quits instantly now. I hope somebody can help!

Thanks.

Try rebuilding, it might magickally fix the problem. Make sure the dlls are in the same folder as the executable too.

How? In your code, it is declared and initialized to false on the same line.

Personally, I use a variable called "running" instead, so the game loop ends when !running.