> The problem not in "sources" file but "empty" /etc/apt/sources.list
That is not the case. You can easily verify this by testing with an empty /etc/apt/sources.list, and /etc/apt/sources.list.d/ubuntu.sources which contains: Types: deb URIs: http://archive.ubuntu.com/ubuntu Suites: mantic mantic-updates Components: main universe Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg Types: deb URIs: http://security.ubuntu.com/ubuntu Suites: mantic-security Components: main universe Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2047447 Title: No valid source.list found while upgrading from mantic to noble To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/python-apt/+bug/2047447/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
