Failed to fetch upgrade to 19.04
132495
14.04.5 to 16.04 Update failed - xenial.tar.gz.gpg missing
12368
A "failed to fetch" error occurs when apt-get update is run. How do I fix this?
24603
apt-get upgrade gives "403 forbidden" error
5316
Update from 14.04 to 16.04 failed with GPG error
2670
Why is "No new release found" when upgrading from a LTS to the next?
134080
Still can't upgrade? Is there a new delay?
15687
How do I resume a release upgrade?
1520
How to install software or upgrade from an old unsupported release?
29191
Upgrade to 18.04 from 17.10
10633
software updater failed to download repository information
139589
Unable to update Flash
129101
Upgrading Ubuntu 9.04 to 9.10 when Update Manager doesn't let you
65099
Unable to install any updates through update manager/apt-get upgrade
64509
Can't update from official repositories [Error 409]
152158
failed to fetch security undermined error [IP: 91.189.91.38 80] in ubuntu 20.04
129223
Ubuntu upgrade from 17.04 to 18.04
4853
Trouble downloading packages list due to a "Hash sum mismatch" error