|I have no idea what you mean by 'I think a special one that I don´t know'.|
Error 550 implies that the server at the Hotmail end is not responding, possibly because the account does not exist. Have you checked that you are using the correct username/password? Have you not used it for a long time, the account may have lapsed?
"I've always been mad, I know I've been mad, like the most of us..." Pink Floyd