Snap update errors [duplicate]

Could you submit the content of /var/log/syslog once you run sudo snap install lxd?

To do so, open a terminal and type:

$ grep snap /var/log/syslog

Solution #1

Usually, when this error occurs, you can resolve it by removing your credentials from ~/.snap/auth.json and by trying to re-authenticate.

Edit:

First, try to stop snapd

$ sudo systemctl stop snapd.service

Take a back-up and remove the /var/lib/snapd/state.json

$ sudo mv /var/lib/snapd/state.json /var/lib/snapd/state.json.bck

Start again snapd

$ sudo systemctl start snapd.service

$ snap login

Update all Snap packages

$ snap refresh

Remove broken Snap

$ snap remove lxd

Try to install lxd again

$ snap install lxd

You could try installing lxd with the sudo prefix as shown below:

sudo snap install lxd