recently I ran into a problem which seemed pretty similar to that described in this post:
I was receiving this error message anyway-
Requires installation of untrusted packages: The action would require the installation of packages from not authenticated sources.
I had tried to download installations and updates from a variety of different sources, but all returned the same message. Likewise
sudo apt-get update/upgrade/install failed. So I tried what was suggested in the above post:
sudo apt-get clean cd /var/lib/apt sudo mv lists lists.old sudo mkdir -p lists/partial sudo apt-get clean sudo apt-get update
But then when I open software center the install button has disappeared, not greyed out, totally missing.
From terminal, if I try to install anything, it returns
Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package
W: Failed to fetch http://ftp.heanet.ie/pub/ubuntu/dists/precise-security/universe/i18n/Translation-en Unable to connect to 18.104.22.168:80: E: Some index files failed to download. They have been ignored, or old ones used instead.
This maybe an awful noob statement, but that IP address stays the same no matter what server I direct update manager to download from.
Finally, upgrade, for what it's worth, returns:
Reading package lists... Done Building dependency tree Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
I also uninstalled Ubuntu software, hoping against hope that somehow I'd get it reinstalled and somehow that would fix everything.
I'm a bit out of my depth here and would very much appreciate any help anyone can give me. I really hope there is some way to fix this problem without reinstalling the OS.