[cups] Cups usb printer discovery problems

[Eugene Prokopiev]

>> Run "cupsctl --debug-logging" and then look at /var/log/cups/error_log when you go to add the printer.
>
> I can't see nothing interesting in error_log, so I attached it.

Sorry, previous file was wrong, so I attached another one. The
interesting part looks like:

D [09/Sep/2014:17:31:33 +0400] [CGI] list_devices
D [09/Sep/2014:17:31:33 +0400] [CGI] libusb_get_device_list=7
D [09/Sep/2014:17:31:33 +0400] [CGI] Failed to open device, code: -3

It looks as permissions problem, but how can it be with root privileges?

-- 
WBR,
Eugene Prokopiev