How-To Geek

Sorry for the really stupid post. I recently got a new computer. It has linux mint. Anyway, when I first got it about a week ago, I set it up with only one account- mine- the admin account. So I am off of the computer for a week, and I go to log back in, and it says either wrong user name or wrong password. Eventually I reset my password via http://community.linuxmint.com/tutorial/view/339 .... So I know it isn't the password. I have tried everything for the username. I do not have an installation disk or anything to reinstall from. Any ideas how I could figure it out or reset it. If there's something I can go to in GRUB like how I reset the password, and you tell me the directions I could probably do it. I can figure out how to do command prompt. Any help would be great!
Oh, and I do not have the CD. I bought it as is from the store.

Linux Mint, as many other Linux distributions, is free to download and use: http://linuxmint.com/

If you want to reinstall and need any help ask us.

EDIT: I just saw OP was 2 weeks ago :D .