I CANT ACTIVATE IT!
I rent the room where tiber septim sleeps and i sleep till 1 am like how it's instructed, but the lady at the inn never screams triggering the appearence of tiber septim's old ghost.
the mission where u have to retrive hjalti, an old sword to one of tiber septim's old companions..
but i try to sleep in his room and the quest never activates
any help?

The quest might be glitched in a way the programming is arguing with itself and won't start.
My dad can't start the legion missions because the Fort you clear out initially is cleared out but the programming says that it isn't cleared yet.

You'll probably have to skip/ignore that mission. Restart a previous save and do again it might help.

The location of the sword is randomly generated and there are several possibilities, some of which are also the targets of other quests. I know there are issues with other groups of side quests where if they share the same possible locations, you can't get an additional one while you already have one of them active and uncompleted. Maybe this is another one of those things... do you have any other quests with target locations in the Reach? If so, maybe that's blocking the innkeeper from giving you the quest for the sword. Just a wild guess though.

^ This.... I'd second that guess.