I am using WSL (windows-for-linux) with installed Ubuntu 20.04.3 LTS.
When I run sudo apt-get update
I get following error:
Err:7 https://apt.kitware.com/ubuntu bionic InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 6AF7F09730B3F0A4
Fetched 11.0 kB in 1s (7552 B/s)
I tried the tips posted in:
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY
but that does not work for me - gpg complains about "no data":
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 6AF7F09730B3F0A4
Executing: /tmp/apt-key-gpghome.Cz3vHTxU7i/gpg.1.sh --keyserver keyserver.ubuntu.com --recv-keys 6AF7F09730B3F0A4
gpg: keyserver receive failed: No data
What shall I do to make apt-get update work?
UPDATE:
As requested I share /etc/apt/source.list
deb http://archive.ubuntu.com/ubuntu/ focal main restricted
deb http://archive.ubuntu.com/ubuntu/ focal-updates main restricted
deb http://archive.ubuntu.com/ubuntu/ focal universe
deb http://archive.ubuntu.com/ubuntu/ focal-updates universe
deb http://archive.ubuntu.com/ubuntu/ focal multiverse
deb http://archive.ubuntu.com/ubuntu/ focal-updates multiverse
deb http://archive.ubuntu.com/ubuntu/ focal-backports main restricted universe multiverse
deb http://security.ubuntu.com/ubuntu/ focal-security main restricted
deb http://security.ubuntu.com/ubuntu/ focal-security universe
deb http://security.ubuntu.com/ubuntu/ focal-security multiverse
deb https://apt.kitware.com/ubuntu/ bionic main