When I do the command below:
sudo apt-get upgrade
At the bottom I get an error saying
W: GPG error: http://download.opensuse.org Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 8873E7BF70F1BBEA
How do I retrieve this key from the opensuse.org server? If I were to look on their website I won't be able to find the key. There are so many nested directories on the website, and I don't know where to look to find it. I don't even know what application or what update it's even for.
Update
I have followed the guides in the comments and it doesn't work. I moved my lists file, and created a new one when using apt-get update. I now have 15 PPA files, and 16 security files. After removing some of the other GPG keys, I now have even MORE errors when updating.
/var/lib/apt/lists
directory, it'll cause that error. – RPiAwesomeness Nov 07 '15 at 19:36dpkg -l | awk '/^ii/ {system("apt-cache policy " $2)}' > out
. Post the content ofout
here http://paste.ubuntu.com/ and give me the link – A.B. Nov 07 '15 at 20:09