I am not able use my Ubuntu Software Center and Synaptic package manager. I can't understand what's the problem. When I use the command: sudo apt-get update it shows this error: E: Malformed line 1 in source list /etc/apt/sources.list.d/canonical_partner.list (dist parse) E: The list of sources could not be read. I have seen How do I remove a malformed line from my sources.list?, but it didn't help.