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I have recently loaded Ubuntu from a CD. My administrator password doesn't work when logging into Ubuntu at the opening screen.

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marked as duplicate by Eliah Kagan, Basharat Sialvi, jokerdino Aug 18 '13 at 18:28

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Normally, you would not have (or need) an administrator password. The proper way to perform administrative tasks is by using "sudo" or ("gksudo" for graphical apps). – Marty Fried Sep 1 '12 at 3:53
    
Are you able to log in at all? Or are you only able to use the "guest" account? – Eliah Kagan Sep 1 '12 at 3:56

Boot while holding the shift key down. You'll then be greeted by a GRUB menu. You want to select boot recovery mode. Once in recovery mode you can passwd yourusername to set a new password.

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same problem! L am getting "authentication token manipulation" messages. Don't know what this means. – carol butler Sep 3 '12 at 3:18

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