Can't open Software Center or Update Manager

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http://askubuntu.com – When I try to (not from terminal) the following error message opens up: An unresolvable problem occurred while initializing the package information. Please report this bug against the 'update-manager' package and include the following error message: 'E:Malformed line 60 in source list /etc/apt/sources.list (dist parse)' Using Ubuntu 12.04, thanks. (HowTos)