Cannot Update packages
6809
How do I fix the GPG error "NO_PUBKEY"?
129101
Upgrading Ubuntu 9.04 to 9.10 when Update Manager doesn't let you
30645
How to install (old) packages for Ubuntu 9.04?
32426
How to install packages?
117852
"Package dependencies cannot be resolved" error when installing software
85009
`apt update` failed on Debian Linux
19288
Update manager doesn't offer an upgrade to the new release
65099
Unable to install any updates through update manager/apt-get upgrade
127766
how to upgrade my Debian package with minor changes
13054
Failing package manager?
102559
How to install package from newer distribution?
108510
apt-get update very slow, stuck at "Waiting for headers"
11166
"Require Installation Of Untrusted Packages" while upgrading with the update manager
93942
How to fix "Failed to download repository information" error while updating?
4268
How to fix "Package is in a very bad inconsistent state" error?
94171
Why Does Software Updater Say No updates Available, but apt-get upgrade Shows updates available?
135985
Apt-get saying "Unable to correct problems, you have held broken packages."