If go thru NextCloudPI WebUI to update NextCloudPi or NextCloud running by NextCloudPi in Docker, errors could be occurred, which can lead the user not found error. The correct way to do is recreate container using new image.
/data in container must be mapped or backed up.
Update NextCloudPI Image
docker image pull ownyourbits/nextcloudpi-x86
Remove existing container
docker stop nextcloudpi docker rm nextcloudpi
Use the previous docker parameter, make sure
/data was mapped.
docker run -d -p 4443:4443 -p 443:443 -p 80:80 -v /app/nc/data:/data --name nextcloudpi ownyourbits/nextcloudpi-x86 $IP
Login to NextCloudPi, the NextCloudPi will update itself, need to wait for the process
Restore data from backup (If required)
Backup => nc-backup-auto in NextCloudPi WebUI, to find out the backup path, and restore the latest if required.
Manual Update NextCloud
Updates => nc-update-nextcloud in NextCloudPi WebUI, to update NextCloud Manually.