karmic upgrade gone bad
Ok I tried up grading last night my computer mouse froze and so I decided to down grade with a disk I had at the house. The downgrade worked, kind of my, mouse works but know I cannot log in. I tried the recovery password protocol and I get the following message: unknown user.
Is there anyone to recovery the password
How do I get a fresh or clean down load of Ubuntu
Any suggestions on how to fix it or get the system to work ,even if I have to lose everything that is on the computer?