CUPS denies access to printer

I've got a printer hooked up to my workstation (running PCLINUXOS2012) by USB. All was well until the last time I tried to apply updates to the packages - it went rather pear shaped - lots of upgrade packages were no longer available from the repositories (this may be coincidental to the printing problem). Since then, only root can see the printer via CUPS unless I make it available to others: [colin@localhost ~]$ lpq lpq: error - no default destination available. [colin@localhost ~]$ su Password: [root@localhost colin]# lpq HP-Deskjet-F4200-series is ready no entries [root@localhost colin]# lpadmin -p HP-Deskjet-F4200-series -u allow:all [root@localhost colin]# su colin -c lpq HP-Deskjet-F4200-series is ready no entries [root@localhost colin]# (but this does not change the cupsd.conf - hence needs to be re-applied each time the system is rebooted). How do I make the change permanent? (Coincidentally, the tool used to configure printers accessed from drakconf (PCLinuxos Control centre) now bombs out with the message "The program terminated abnormally). cupsd.conf below, apologies for repodrucing it in it's entirety, but the running version clearly does not match the documentation supplied (which, for example, reports that 'Browsing' can be 'Yes' or 'No', but nothing get's logged for a value of 'on'). I would have expected the lines below the comments to make the printer available to all - but this does not appear to be the case. LogLevel warn SystemGroup lpadmin root Group sys User lp Port 631 Listen /var/run/cups/cups.sock Browsing On BrowseAddress @LOCAL BrowseOrder allow,deny # this line to make printers 'browseable'.... BrowseAllow all BrowseLocalProtocols CUPS dnssd DefaultAuthType Basic Order allow,deny # this to allow access to the web frontend.... Allow all AuthType Default Require user @SYSTEM # and this one to allow submission of print jobs... Allow all Order deny,allow Require user @OWNER @SYSTEM Order deny,allow AuthType Default Require user @SYSTEM Order deny,allow AuthType Default Require user @SYSTEM Order deny,allow Require user @OWNER @SYSTEM Order deny,allow Order deny,allow AuthType Default Order deny,allow AuthType Default Require user @OWNER @SYSTEM Order deny,allow AuthType Default Require user @SYSTEM Order deny,allow AuthType Default Require user @SYSTEM Order deny,allow AuthType Default Require user @OWNER @SYSTEM Order deny,allow Order deny,allow