I'm trying yo upgrade 18.04LTS to 20.04LTS.
What I've done in preparation:
- Comparing my sources.list with this (identical except us→nl subdomains)
sudo apt update
sudo apt install -y update-manager-core
sudo apt-get --with-new-pkgs upgrade
sudo apt remove wine-stable
(package with unmet dependencies)sudo apt autoremove
sudo apt-get dist-upgrade
(didn't perform anything)sudo apt-get upgrade
(because people say either apt or apt-get does more than the other)- Reboot
Then its giving me this error:
mark@mark:~$ sudo do-release-upgrade -d
Checking for a new Ubuntu release
Get:1 Upgrade tool signature [1554 B]
Get:2 Upgrade tool [1342 kB]
Err Upgrade tool
Undetermined Error [IP: 213.136.12.213 80]
Fetched 1554 B in 0s (0 B/s)
authenticate 'focal.tar.gz' against 'focal.tar.gz.gpg'
Authentication failed
Authenticating the upgrade failed. There may be a problem with the network or with the server.
Searching with some of the key terms above gives 0 results on google.
There's no problem with my network, and there's plenty free disk space.
I tried removing /etc/apt/trusted.gpg
, re-adding official Ubuntu keys, and doing apt-update. This succeeded, but it didn't help with the error above.