Was cups installed & running before?
I guess so as logout/login would be orthogonal to that.
Could you attach (not paste) the output of the following command?
journalctl > /tmp/journal.txt

@Colin & Olav:
It might be that gtk+ does'n't see cups.
Or an issue with udev?

Keywords: (none) => NEEDINFO
CC: (none) => mageia, olav, thierry.vignaud
Component: Release (media or process) => RPM Packages

There's a newer GTK+ version which fixes things for Avahi. See message on dev. This is about USB though, so guess different issue?

We can always push the new version in core/updates_testing and test it...

I've just installed RC and couldn't get it to pick up my HP printer so I ran the command in comment 1 but no output appeared, so I ran less /tmp/journal.txt and I'll attach the result of that.

CC: (none) => cmrisolde

Created attachment 5962 [details]
output of "less /tmp/journal.txt"

Silly me, I was getting tired and my brain wasn't working, I could have just attached the file, couldn't I :)  Let me know if that would be easier to read.

This bug has much in common with 1454 (re-opened), 14440, and 15549!

I've just done a KDE install of 32-bit 'classic' Mageia-5RC (23/3/15 
version) on my laptop (real h/w). Then did full s/w update.

With USB HP5520 printer 'off', I started system-config-printer, which 
installed a bunch of printing packages and HP utilities.
  I then switched the printer on. 
RESULT: After over a minute, no signs of the printer in Add Printer.

So left printer 'on', exited system-config-printer, and then started it 
again.
RESULT: Add Printer popped up the printer info within 5 seconds, and 
after the rigamarole described earlier the selection of the 'HP Scanning 
& printer... (HPLIP)' option eventually completed the installation, 
which HPLIP accepted.

So - no need to reboot, just a lot of patience!

(Same experience with 64-bit version.)

CC: (none) => maurice

> no need to reboot, just a lot of patience.

Yesterday (with the 29/3 64-bit Mageia-5RC (KDE, on live h/w)) SCP 
excelled itself.
  What happened was that - no matter how many times SCP was restarted - 
it would not pop up the HP5520 ID line, so I tried a reboot.

And - believe it or not - it then promptly installed, with no questions, 
the HP1050 USB printer connected to another PC on our LAN!!! No sign of 
mine.
  (I didn't know whether to laugh or cry...)

However, when I hit 'Add Printer' again it did then pop up the HP5520 
line and the now familiar but laborious and lengthy install rigmarole eventually installed my own USB printer (accepted by HPLIP).

N.B. Out of curiosity I then fired up the 2012 PCLinuxOS I still have 
lying around, and asked it to install the HP5520, which it went on to find in 
a flash and install in under a minute (though HPLIP would not then 
acknowledge it).

With recent installs of Mageia-5RC (ISO's dated 29/3 & 1/4), after SCP has installed the various printer packages it has consistently failed to detect any USB printer until a reboot, when - much to my astonishment (I had never seen this before)- as soon as I started SCP (and BEFORE hitting 'Add printer') it showed a 'printer installed' icon for a USB HP1050 printer attached to a LAN PC in another room!! 

(If I then hit 'Add Printer' it quickly finds my own printer and offers the "HPLIP Scanning & Printing...(HPLIP)" option as well as "USB".)

(What is the point of the confusing "USB" option? Does it simply mean "non-HPLIP"?)

As for the 'HPLIP' option, it is often appears to freeze several times, for 1-2 minutes, between several info messages that "Systemd wants to install <some 'libsane' package>". Puzzlingly, the msg shows only 'Cancel' and 'Close' options the first time or two, then eventually an 'Install' option, after which the install eventually completes.
  
All the above occur both with both 64-bit (on real h/w PC) and 32-bit (real h/w on laptop).

For newcomers to Mageia it will be a great puzzle and frustration, and for Mageia an embarrassment - especially in reviews.

WHAT TO DO ABOUT THIS?
  
 If - instead of returning to SCP after it has installed the first lot of printer packages - one starts HPLIP instead, it does the install smoothly and quickly.  For myself, I shall use that workaround for routine installs.

But I wouldn't like to be a newcomer to Mageia trying to get a USB HP printer installed. How is he going to understand the HPLIP v. USB options of Add Printer, and the apparent need to reboot after first using SCP?
  And what will he make of the interminable delays during Add Printer's 'HPLIP' option? Probably that it has 'bombed out'...

Still valid according to reports in qa-discuss

And with classical 64-bit .iso of 15/6, as I've just found.

I've just retested this with the final release.

The issue with 'localhost' being the only option available when you try to connect to a server is still present, but in my tests is resolved by simply restarting system-config-printer - no need to log out.

The issue with the printer not being detected after you click on Add should have been fixed by the patches in bug 15549. In my tests, my HP printer was correctly detected and installed. So unless Ben reports otherwise, I'd say this has been resolved.

As discussed in qa-discuss, Maurice's problem was something different.

Is the issue with connecting to a server important enough to warrant an errata entry? I've never used that feature myself.

CC: (none) => mageia

for the final final round of classical seems to be ok

Status: NEW => RESOLVED
Resolution: (none) => FIXED