Whenever I shut down my pc, a message appears on screen saying other people are logged onto my computer, shutting down may cause them to lose data, do i want to continue shutting down anyway? I've been getting this for a while. My mum has recently changed her pc and has xp for the first time, and she has started to get the same? Is someone up to something thay shouldnt be with my pc? Has anyone else experienced this? It makes me uneasy??