System went to sleep, then asked for a password. I have tried every password I have ever used. Does ubuntu require something different. I loaded this two years ago, last summer. I do not remember, how do I get it back?
I would boot from a System Rescue CD (http://www.sysresccd.org) and mount your filesystem, chroot into it and then change the password.
This is done like so:
Note that there are many ways in which this procedure can go wrong. Refer to the excellent documentation at http://www.sysresccd.org/Online-Manual-EN for how to handle LVM, etc.