sudo apt-get update I get the error shown below.
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://dl.winehq.org/wine-builds/ubuntu bionic InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 76F1A20FF987672F W: Failed to fetch https://dl.winehq.org/wine-builds/ubuntu/dists/bionic/InRelease The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 76F1A20FF987672F W: Some index files failed to download. They have been ignored, or old ones used instead.
So I go ahead and change my mirror as suggested by this Ask Ubuntu answer. Then I restart the computer. And I still get the same error above when I
sudo apt-get update.
Let's try and reinstall the keys.
$ wget -nc https://dl.winehq.org/wine-builds/Release.key && sudo apt-key add Release.key File ‘Release.key’ already there; not retrieving. OK
And I might as well
ping -c3 archive.ubuntu.com and my packet loss is 0%. What else do I need to do?