a vague guess of mine is questhelper.... and he means the ? on the map
so that means that you disabled questhelper as an addon in your login screen or somehow disabled it ingame (dont know how that is done, cause i dont use it anymore ... other people here should be able to help you on that)
greetings
T
p.s. for the future: when you have a question, a bit more information "could" be helpful.
EDIT: my guess was right. OP edited his post.