2 HP printers only printing grayscale

[ElViejito]

Clean installation of Centos 7 on an HP desktop 64bit AMD processor. Also, one
HP All-In-One 7520 printer and one HP All-In-One C5180 printer. Trying different
color files generated by different programs produces only grayscale. Color is
enabled on both printers. A windows laptop successfully prints in color to
both printers through the same router that the desktop uses. Both printers
installed through Centos 7; KDE and GNOME yield the same result.

When I shut down the computer and reboot, Centos 7 still prints only in
grayscale. But then if I go to Administration/Print Settings (using KDE),
authenticate as root and press OK (making no changes), I can now print in color.

An additional odd thing about this is that I have to authenticate as root 2x;
after entering the first root password, another authenticate popup appears
requesting root authentication. Once I authenticate the second time and
press OK, I can now print in color.

Since no one else reports this problem, I'm guessing I have some faulty code.
If anyone could suggest what code or rpm sections
need to be re-installed, I would greatly appreciate it. I'd rather avoid
re-installing the entire OS.

This was posted earlier in Software Support Forum with no response.

Thanks.

[gerald_clark]

Yes, you posted here: viewtopic.php?f=48&t=52760&p=224042#p224042
So don't post again here.