Sorry to hear that but glad it worked out for you. I plucked up the courage to try the update with quite a few gigabytes to do as I had been holding off. The gnome software route failed because to add to the peril there was a Nvidia update too! So reverted to dup & accepting those licences & fortunately it rebooted OK for me. SO maybe if you have nothing in the nssswitch.conf file then you’ll be fine? The only annoyance I had was as others have observed in another thread was in relation to the upgrade of Evolution. This meant I had to re authorise my outlook e-mail in the online accounts, which proved a bit troublesome, but I got there in the end. hurrah & a happy weekend to all.