You can add your user to the sys group in PCC > System > Manage users. However, I haven't had to for printer or CUPS use. Is your user a member of lp, lpadmin and usb groups? Do you have the hplip, hplip-common, hplip-hpijs, printer-tools and printer-utils packages installed?
I am confused on some of this, I'm sure I have been added but I may be looking in the wrong place. Remember I'm older then op, my eyes are worse, and my wife states I'm slow, real slow.
I'm real sorry about that, but the doctors don't give me a time for how long I will be able to use a computer. They want to do so many operations on my eyes and do not guarantee that my sight
will improve or I will be able to see after their work. When I look at the eye chart for them no
matter what they do it is nothing but a blur. I have to use all sorts of magnification and glasses
to run, type and use a computer now. ( don't get old, and hopefully live a hard young life ).