Unable to update Plesk Obsidian to the latest version with the following error:
Error: There is no release with ID 'PLESK_18_0_35' of product 'plesk' at the installation source
Error: Unable to receive update information for the package(s)
Notification with the error regarding the failed update is sent to Plesk admin over email:
Some problems occurred with the System Updates tool on your server. Please resolve them manually.
INFO: pum is called with arguments: ['--list', '--repo-info', '--json']
W:The repository 'http://autoinstall.plesk.com/PHP73_17 xenial Release' does not have a Release file.
W:Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
W:See apt-secure(8) manpage for repository creation and user configuration details.
E:Failed to fetch http://autoinstall.plesk.com/PHP73_17/dists/xenial/all/binary-amd64/Packages 404 Not Found
E:Some index files failed to download. They have been ignored, or old ones used instead.
ERROR: Exited with returncode 1.
Ubuntu 16.04 is installed on the server. Ubuntu 16.04 reached End-of-life on April 30th, 2021.
The latest supported version of Plesk Obsidian for Ubuntu 16.04 is 18.0.34, so no further Plesk updates are available.
Apply one of the possible solutions:
Perform a dist-upgrade from Ubuntu 16.04 to Ubuntu 18.04.