Trying to upgrade from 12.10 to 14.04 and not having any luck...404 error occurs
1520
How to install software or upgrade from an old unsupported release?
5820
How to fix the “Unable to calculate upgrade” issue from command line when upgrading from 12.04 to 14.04?
157904
error 503: service unavailable when using apt-get update behind proxy
77692
How do I update Drush to the latest available version?
119595
Is it necessary to upgrade to 14.04 LTS or can I stand in 12.04 LTS forever with no problem?
7357
upgrade to 13.10 stalled and restart failed
65099
Unable to install any updates through update manager/apt-get upgrade
86777
Distribution upgrade problem "No new release found"
50810
No upgrade available for 19.04 from 18.10
35243
Is it safe to do-release-upgrade from 12.04.4 to 14.04.1?
150104
Unable to download software center from package manager: 404 Not Found
13720
apt-get update fails to fetch files, “Temporary failure resolving …” error
11909
404 error with apt-get update, Don't have any PPA's
421
How do I update a Drupal distribution to a newer version?
30754
Cannot update: "No available releases found"
59088
How to upgrade to a newer release of Ubuntu using the Live CD?
61473
Failed to fetch because of size mismatch error while upgrading