I have a new server installation of Ubuntu Server 20.04 but when I try run an update I get the following error.
sudo apt update
Get:1 http://gb.archive.ubuntu.com/ubuntu focal InRelease [265 kB]
Get:2 http://gb.archive.ubuntu.com/ubuntu focal-updates InRelease [114 kB]
Get:3 http://gb.archive.ubuntu.com/ubuntu focal-backports InRelease [101 kB]
Get:4 http://gb.archive.ubuntu.com/ubuntu focal-security InRelease [109 kB]
Err:1 http://gb.archive.ubuntu.com/ubuntu focal InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 3B4FE6ACC0B21F32 NO_PUBKEY 871920D1991BC93C
Err:2 http://gb.archive.ubuntu.com/ubuntu focal-updates InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 3B4FE6ACC0B21F32 NO_PUBKEY 871920D1991BC93C
Err:3 http://gb.archive.ubuntu.com/ubuntu focal-backports InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 3B4FE6ACC0B21F32 NO_PUBKEY 871920D1991BC93C
Err:4 http://gb.archive.ubuntu.com/ubuntu focal-security InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 3B4FE6ACC0B21F32 NO_PUBKEY 871920D1991BC93C
Reading package lists... Done
W: http://gb.archive.ubuntu.com/ubuntu/dists/focal/InRelease: The key(s) in the keyring /etc/apt/trusted.gpg.d/ubuntu-keyring-2012-archive.gpg are ignored as the file has an unsupported filetype.
W: http://gb.archive.ubuntu.com/ubuntu/dists/focal/InRelease: The key(s) in the keyring /etc/apt/trusted.gpg.d/ubuntu-keyring-2012-cdimage.gpg are ignored as the file has an unsupported filetype.
W: http://gb.archive.ubuntu.com/ubuntu/dists/focal/InRelease: The key(s) in the keyring /etc/apt/trusted.gpg.d/ubuntu-keyring-2018-archive.gpg are ignored as the file has an unsupported filetype.
W: GPG error: http://gb.archive.ubuntu.com/ubuntu focal InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 3B4FE6ACC0B21F32 NO_PUBKEY 871920D1991BC93C
E: The repository 'http://gb.archive.ubuntu.com/ubuntu focal InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: http://gb.archive.ubuntu.com/ubuntu/dists/focal-updates/InRelease: The key(s) in the keyring /etc/apt/trusted.gpg.d/ubuntu-keyring-2012-archive.gpg are ignored as the file has an unsupported filetype.
W: http://gb.archive.ubuntu.com/ubuntu/dists/focal-updates/InRelease: The key(s) in the keyring /etc/apt/trusted.gpg.d/ubuntu-keyring-2012-cdimage.gpg are ignored as the file has an unsupported filetype.
W: http://gb.archive.ubuntu.com/ubuntu/dists/focal-updates/InRelease: The key(s) in the keyring /etc/apt/trusted.gpg.d/ubuntu-keyring-2018-archive.gpg are ignored as the file has an unsupported filetype.
W: GPG error: http://gb.archive.ubuntu.com/ubuntu focal-updates InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 3B4FE6ACC0B21F32 NO_PUBKEY 871920D1991BC93C
E: The repository 'http://gb.archive.ubuntu.com/ubuntu focal-updates InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: http://gb.archive.ubuntu.com/ubuntu/dists/focal-backports/InRelease: The key(s) in the keyring /etc/apt/trusted.gpg.d/ubuntu-keyring-2012-archive.gpg are ignored as the file has an unsupported filetype.
W: http://gb.archive.ubuntu.com/ubuntu/dists/focal-backports/InRelease: The key(s) in the keyring /etc/apt/trusted.gpg.d/ubuntu-keyring-2012-cdimage.gpg are ignored as the file has an unsupported filetype.
W: http://gb.archive.ubuntu.com/ubuntu/dists/focal-backports/InRelease: The key(s) in the keyring /etc/apt/trusted.gpg.d/ubuntu-keyring-2018-archive.gpg are ignored as the file has an unsupported filetype.
W: GPG error: http://gb.archive.ubuntu.com/ubuntu focal-backports InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 3B4FE6ACC0B21F32 NO_PUBKEY 871920D1991BC93C
E: The repository 'http://gb.archive.ubuntu.com/ubuntu focal-backports InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: http://gb.archive.ubuntu.com/ubuntu/dists/focal-security/InRelease: The key(s) in the keyring /etc/apt/trusted.gpg.d/ubuntu-keyring-2012-archive.gpg are ignored as the file has an unsupported filetype.
W: http://gb.archive.ubuntu.com/ubuntu/dists/focal-security/InRelease: The key(s) in the keyring /etc/apt/trusted.gpg.d/ubuntu-keyring-2012-cdimage.gpg are ignored as the file has an unsupported filetype.
W: http://gb.archive.ubuntu.com/ubuntu/dists/focal-security/InRelease: The key(s) in the keyring /etc/apt/trusted.gpg.d/ubuntu-keyring-2018-archive.gpg are ignored as the file has an unsupported filetype.
W: GPG error: http://gb.archive.ubuntu.com/ubuntu focal-security InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 3B4FE6ACC0B21F32 NO_PUBKEY 871920D1991BC93C
E: The repository 'http://gb.archive.ubuntu.com/ubuntu focal-security InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
I did try look around for a solution and some users resolved the issue using the following command but I get an error
sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 871920D1991BC93C
/usr/bin/apt-key: 328: cmp: Exec format error
/usr/bin/apt-key: 330: cmp: Exec format error
/usr/bin/apt-key: 332: cmp: Exec format error
/usr/bin/apt-key: 328: cmp: Exec format error
/usr/bin/apt-key: 330: cmp: Exec format error
/usr/bin/apt-key: 332: cmp: Exec format error
/usr/bin/apt-key: 328: cmp: Exec format error
/usr/bin/apt-key: 330: cmp: Exec format error
/usr/bin/apt-key: 332: cmp: Exec format error
Executing: /tmp/apt-key-gpghome.Nnj6QeHxYv/gpg.1.sh --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 871920D1991BC93C
gpg: connecting dirmngr at '/tmp/apt-key-gpghome.Nnj6QeHxYv/S.dirmngr' failed: IPC connect call failed
gpg: keyserver receive failed: No dirmngr
W: The key(s) in the keyring /etc/apt/trusted.gpg.d/ubuntu-keyring-2018-archive.gpg are ignored as the file has an unsupported filetype.
I've never had this type of issue before and now I'm lost on how I can resolve it. Any help would be appreciated.
