FindGameObjectsWithTag Error

Hi guys, in my scene I want to disable some scripts assigned to some GameObjects when I click the “Escape” button. All those GameObjects are tagged “Enemy” and the script that I want to disable is called “Following”. How can I do?

void Update()
    {
		if(Input.GetKeyDown(KeyCode.Escape))
                 disable();
    }
void disable()
    {

    }

In C#:

void disable()
{
    foreach ( GameObject enemy in GameObject.FindGameObjectsWithTag( "Enemy" ) )
    {
        enemy.GetComponent<Following>().enabled = false;
    }
}