Thats a temporary mirror problem, not an issue with Ubuntu. Thanks for reporting though, and feel free to do so again in the future.
** Changed in: update-manager (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/784466 Title: ubuntu.otenet.gr repository fails to upgrade with 404 Not Found -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs