In my freshly installed Ubuntu 20.04 LTS, Ubuntu Software is not loading properly.
It is loading only Editor's Picks but nothing else.
Installed tab is empty and search is not working as well.
My internet connection is perfectly working and I am not using any firewall.
I just finished the installation of the Ubuntu 18.04, but whenever I try to install any application from Ubuntu Software the same error occurs (for example "vlc"):
unable to install "vlc": snap "vlc" has "install-snap" change in progress
I hope somebody can tell me what I've done wrong.
How do I get to the Universe Repository in supported versions of Ubuntu?
Any install that I'm trying through the Software Center is telling me:
Requires installation of untrusted packages: The action would require the installation of packages from not authenticated sources.
I did an apt-get update from the command line, then removed the software sources that the keys were bad from (PPAs I added myself), and unchecked them in the software sources for software center, but to no avail. I can't install anything from software center anymore - only> from the command line with apt-get.
Is uninstalling/installing the only option? I don't want to break other PPAs that I have.
Here's a paste from apt-get update:
Reading package lists... Done
W: GPG error: http://ppa.launchpad.net oneiric Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B725097B3ACC3965
W: GPG error: http://us.archive.ubuntu.com oneiric Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key <[email protected]>
I've tried apt-key update, and there was no effect (two keys unchanged).
The output of apt-get update and apt-get upgrade, and the contents of /etc/apt/sources.list, can be found in this pastebin post.
Every second e-mail I get suggests to download Adobe Acrobat reader, but adobe.com doesn’t provide a Linux version.
Which PDF Viewer are there available for Ubuntu?
I’m fine with partial solutions, a perfect match however would not only display PDF files, but also be able to: