update on ubuntu 14.04 "E: Some index files failed to download. They have been ignored, or old ones used instead."
133
How can I fix a 404 Error when using a PPA or updating my package lists?
35190
"Software Updater" & "Software & Updates" not working
40885
What should I do when I got the KEYEXPIRED error message after an apt-get update?
64509
Can't update from official repositories [Error 409]
135985
Apt-get saying "Unable to correct problems, you have held broken packages."
65099
Unable to install any updates through update manager/apt-get upgrade
99687
update-alternatives --install says it needs link name path priority?
1632
How do I fix a "Failed to download package files" error?
117112
Why isn't Ubuntu moving its repositories to old-releases anymore?
17208
What does this apt error message ("Download is performed unsandboxed as root...") mean?
30226
How to resolve Google "Indexed, though blocked by robots.txt"
100000
QGIS update from 2.14 to 2.16 failed on Ubuntu 14.04
119943
Where can I find a repository for older unsupported releases?
140893
Error when using apt-get update
130118
Ubunutu 18.04 Updates 404 error
122274
Release file for http://archive.ubuntu.com/ubuntu/dists/bionic-updates/InRelease is not valid yet
52190
How and when is old-releases.ubuntu.com updated?