It happened during the weekend, so there is none of the school administrators to help with - but that's not the worst. Such behavior should not be possible and

It happened during the weekend, so there is none of the school administrators to help with - but that's not the worst. Such behavior should not be possible and his daughter should not be able to grant such permissions either. The school =should= know it's not a kid's account to begin with. None of the blame should be attributed to the school but Microsoft - there is no feasible way for the person to reclaim his account. In short - you are missing a lot.