Had the same error. Changed the http://security.ubuntu.com/ubuntu/ to http://archive.ubuntu.com/ubuntu/. Closed and restarted software sources and the problem was corrected.
-- Checking security repository in Updates adds deb line to Third-Party Software https://bugs.launchpad.net/bugs/244093 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
