Yes. You should select the option to log out all users before starting the backup process. If you do not select this option, the backup will not start if someone is using Sage 50 at the time of the scheduled backup. If you check this box and a user is having Sage 50 open at the time of the scheduled backup, he will be logged out without any warning and he will lose unsaved work, if any. Therefore, you should inform all users not to leave Sage 50 open when they wind up for the day.