I filled a duplicate (#88884, sorry), got the exact same error message, and i can confirm that typing
sudo mkdir /root/.gnupg fixed the problem. i was confused because i do have ~/.gnupg for my sudoer user. -- update-manager -d fails to upgrade from 6.10 to 7.04 due to download problems https://launchpad.net/bugs/82464 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs