This bug should only happen due to a buggy proxy on the user's side, or infrequently if the download check happens to take place right as the ports.ubuntu.com site is being updated.
Ubuntu now supports the 'InRelease' signature format on its mirrors, which ensures the signature and signed data are downloaded atomically and are therefore always in sync. debian-installer should use this file in place of the Release{,.gpg} resource pair for verifying mirror integrity. Assigning this bug to the debootstrap package, as it looks like this verification happens in debootstrap-udeb. ** Package changed: debian-installer (Ubuntu) => debootstrap (Ubuntu) ** Changed in: debootstrap (Ubuntu) Status: New => Triaged ** Changed in: debootstrap (Ubuntu) Assignee: Taco Screen team (taco-screen-team) => Mathieu Trudel-Lapierre (mathieu-tl) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1485511 Title: ISST-KVM:CTE:R3-0:raing12: Base system install fails with "Debootstrap Error :Invalid Release signature (key id 40976EAF437D05B5) " using Ubuntu 15.10 latest daily build (20150805) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/debootstrap/+bug/1485511/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs