Hattest du alle Schritte ausgeführt?
+ echo "Cups daemon is now running under \"cups\" user+group."
+ echo "Please make sure to enable the new user+group change in"
+ echo "/etc/cups/cups-files.conf or merge changes from"
+ echo "/etc/cups/cups-files.conf.default. After a service restart"
+ echo "make sure /etc/cups and all files within are owned by"
+ echo "cups group - run \"chgrp -R cups /etc/cups\"."