When I want to install anything in Ubuntu Software Center I get this message :

When I want to install anything in Ubuntu Software Center I get this message :

Try
sudo apt-get update
to update your package list. Then
sudo apt-get autoclean
to clean up any partial packages. Then
sudo apt-get clean
to clean up the apt cache.
sudo apt-get autoremove
will clean up any unneeded dependencies. If while doing this you can identify the broken package this code will very forcefully remove it.
sudo dpkg --remove -force --force-remove-reinstreq package name
Change package name to the real name of course.
sudo: parse error in /etc/sudoers.d/sudoers near line 25 sudo: no valid sudoers sources found, quitting
– Aleksandar Anđelković Oct 07 '11 at 18:47sudo apt-get update– jet Oct 07 '11 at 18:58