Can't install (lost Admin-password)

[Tom Rausner]

Hi!

Hope someone can help me with a serious problem.
By accident the admin password to the authkey on
my wifes computer has been changed, and I don't
know into what.

How can I get around to change it to something
known, without knowing what it is now ? 

She can use the computer with no problems (she
does not have any password on her account), but
it's impossible to install anything new on it.

By the way; administration was done from her
account(in the good days, where it was working) 
using sudo. But then she had a password. Can the
removing of her account password be the reason for
the malfunction ? 

Her computer is running ubuntu 11.10 in the 
"out-of-the-box" configuration.

-- 
Tom Rausner
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             tom at rausner.dk  ICQ:276707843  www.tomtech.dk
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If a person belives he is a monkey, it is called insanity.
If a billion persons belive they are monkies, it is called darwinism.
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