I have a friend who asked me to find out why his mac will not backup using time machine anymore. Here is the problem: Time machine was running fine for a long time and then all of a sudden the other day he noticed it quit backing up and is now getting an error saying his password is not correct and his backups are no longer running. I need to get his backups going for him again but have racked my brain and cannot understand why time machine would be asking for a password. I plan on going over there next week and trying to fix it for him, any ideas what this error is or what I could try to get him backing up again? Thx in advance.