I’ve just spent the last hour battling with Ubuntu to get it to upgrade. My problem stems from installing the World of Goo demo and then removing it (it never had a hope in hell of working on my ATI graphics card). Now every time I try to install a new package through aptitude, or try to perform an upgrade I receive
files list file for package `worldofgoodemo' contains empty filename
I had to remove
/var/lib/dpkg/worldofgoodemo.list
to fix it. Not the most elegant solution, but at least I can install things again.