I think you both missed the point of the original post. He is asking about messenger, not third part messenger clients, but then again you both know that.
It is being such a pain I am going to do a fresh install and fingers crossed it works. If not the air up here will be blue n red with rage and swearing. If it still plays up I will very cross indeed. Forgot how much fun Bills stuff is when it decides to be unco-operative.