Fixing permissions in the CLI worked for me. I had only given the www user (www-data) permissions to the main folder in users directory under the owncloud data directory. Deeper inside, the files and directories were owned by root from when I originally moved them over to the user folder
I used the command “chown -r www-data:www-data *” inside /home/clientdata/user/files/exampledirectory directory and it recursively gave ownership to the www user. I then logged into the web interface and the permissions error notice was gone.