How to fix apt error: NO_PUBKEY FEEA9169307EA071 NO_PUBKEY 8B57C5C2836F4BEB


When running apt update, you see the following error message:

Err:12 gcsfuse-bionic InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY FEEA9169307EA071 NO_PUBKEY 8B57C5C2836F4BEB


This error occurs due to the VirtualBox repo using the outdated (as of April 2022) apt-key method of importing keys.

You can import the key by just installing the gcsfuse repo again. The following commands are based on the official installation guide.

export GCSFUSE_REPO=gcsfuse-`lsb_release -c -s`
echo "deb [signed-by=/usr/share/keyrings/gcsfuse.gpg] $GCSFUSE_REPO main" | sudo tee /etc/apt/sources.list.d/gcsfuse.list
wget -qO- | sudo gpg --dearmor --yes --output /usr/share/keyrings/gcsfuse.gpg

and then running

apt update

again. Note that at the time of writing this post, gcsfuse is not available for Ubuntu 22.04 in the official repository.

You can work around this by installing the bionic packages instead of jammy. For more details, see our post