[SOLVED] How to find and remove packages listed in error message

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http://ubuntuforums.org – Hey all, first post :) When I was brand new to Ubuntu, I downloaded some packages using the APT before fully understanding it. I'm not 100% sure what I did back then, but these packages are causing errors with the 'Software Updater' such that it simply displays an error message, and then closes (however, I am able to update my software using the command line). The error message I get from the software updater is: Failed to Download Repository Information: W:Failed to fetch http://ppa.launchpad.net/ferramrober...source/Sources 404 Not Found , W:Failed to fetch http://ppa.launchpad.net/f (Hardware)