If you dream of pale horses, it can mean some good horses came to send you a message. When was the last contact you had with a horse? What memories does this bring up?
Dream of a white colored horse can mean a good symbol sends you a message of good news. You will see good news in your waking life.
Another dream interpretation of pale horse is that your waking life is surrounded by boring and drab experiences. This can be a good thing if you accept this life style as being safe, albeit boring.
A pale colored horse can also mean it is a metaphorical creature. It is not a real horse, but a representation of one. It has come in your dream to send you a message. You need to reflect to understand the message.