The official arrival days take place on August 17th and 18th. When you arrive in Örebro you need to go to the university by yourself. You can read information about how to get to Örebro University on the University webpage.
There will be an ESN Arrival Camp in Novahuset. There you will meet up with the Student Assistant, fadders and other exchange students. Arrival Camp is open between 11:00 and 22:00 both thursday and friday. During these hours you can ask questions, pick up your keys, eat snacks and hang out! If you have off-campus housing, ESN will drive you there from the university.
If you arrive outside the above stated hours, you need to find a temporary accommodation for the night and then come the following day to collect the keys. This you need to arrange yourself.