Updates requires installation of untrusted packages
6105
What is the easiest way to resolve apt-get BADSIG GPG errors?
31793
The following packages have unmet dependencies!
109539
How can I perform an offline upgrade using Ubiquity on the installation disc?
23096
How to remove obsolete packages after failed release upgrade via do-release-upgrade on Ubuntu?
99687
update-alternatives --install says it needs link name path priority?
73173
How to Fix Broken Packages?
133
How can I fix a 404 Error when using a PPA or updating my package lists?
1632
How do I fix a "Failed to download package files" error?
158791
Bogus message from automatic updates
151656
Installing from source. How to resolve dependencies without destroying the package manager
24603
apt-get upgrade gives "403 forbidden" error
122742
Why does apt-get install a newer dependency than supported by the specified package
131474
How to only install updates from a specific repository?
90937
apt-get update errors
76241
"no public key available" while upgrading using update-manager
135575
How to fix a "Failed to fetch binary-armhf/Packages" error during apt-get update?
117852
"Package dependencies cannot be resolved" error when installing software