You didn't read what RLShare was trying to explain. A user will be shown online until the "Session Timeout" time after their last activity. So, if your user leaves the site, and your Session Timeout is set to 900 (15 minutes), then he will still be shown online for 15 minutes after he leaves. You must have your Session Timeout set to about 60 minutes. You can change that in vboptions > Cookies > Session Timeout