Upgraded to Fedora 31. Printer (HP ENVOY-4500) finally works again after deleting, reinstalling and selecting "USB" connection rather than HPLIP. But xsane can't find the scanner.

First of all, some things you posted do not make sense.

I search on HP's sit for 'HP ENVOY-4500' and got a bunch of hits for many devices, none are a printer/scanner. Please have a close look at the printer, there should be a label with Model and serial number, post the model number.

USB, I'm guessing the printer is USB attached, so its good the printer works.

No idea what you mean by "rather than HPLIP". HPLIP is the set of drivers HP publishes. It does get updated over time, as new printer models are added to the market by HP.You are using one of the drivers from that package, or your printer would not work.

Once we know the actual model of printer, HP publishes the supported devices supported by each HPLIP package. You may have to update HPLIP package, but without the model, no way to tell.

Open a terminal, run the command 'sane-find-scanner' ( just what is between the quotes ). Copy and paste the results into this thread.

So, correct printer model, and run sane-find-scanner.

If sane-find-scanner does not see your scanner, could you run these two commands:

'lsusb' and 'scanimage -L' once again just what is between the quotes and post the results.

Sorry, It's an ENVY-4500. I went to HP's site. Downloaded & installed HPLIP ver 3.19.11 (not available on Fedora repo). Now the scanner works ... but the printer doesn't. The cups server says it printed (enters the que and leaves), but nothing from the printer.

Did you restart cups after the driver update? You can do it either from the command line, or restart your system.
I don't know the command for a restart of cups on a system running system-d.

Yes, restarted the system. And, after restarting a couple times, the scanner option died as well. So, being impatient, I uninstalled the new version of HPLIP, reinstalled the repo version. Now I'm back to where I started: Printer prints, but xsane says "Failed to open device 'hpaio:/usb/ENVY_4500_series?serial=CN45H1420G05X4': Invalid argument.

The 'hp-doctor' utility (part of HPLIP) might be helpful here.

Thanks ferrari (sorry your team didn't do so well in Brazil). Anyway, I've decided it's either a problem with HPLIP, Xsane or cups. And I can't figure it out. Looked for "hp-doctor" couldn't find it. The HPLIP Device Manager doesn't even show a scanner available. I guess for now my printer/scanner is just a printer. Who knows? Some future s/w update might fix it.

Are you referring to Fifa Under-17 World Cup, or something else?

Checking the Fedora HPLIP payload online it doesn't appear to be supplied as part of the package (unlike with openSUSE hplip package).

FWIW, here is HPLIP's diagnostic page...
https://developers.hp.com/hp-linux-i...g/howtos/other

Does /etc/sane.d/dll.conf contain an uncommented entry for hpaio?

Was referring to the Brazil F1.

Yes, there is an uncommented hpaio in /etc/sane.d/dll.d

I'll take a look at that: HPLIP's diagnostic page...

Thanks.

Ah, I don't really follow F1 (although I did work as an audio-visual engineer/contractor in that event many years ago).

Can you report back with output from

Referring to your statement
I note the following advice from this ArchWiki page...
https://wiki.archlinux.org/index.php...valid_argument
In particular...
1) Make sure the user is a member of the 'lp' group (for r/w access to USB-connected scanners).
2) If using a USB 3.0 port try changing to a USB 2.0 port to see whether that makes a difference.
3) Try removing any existing ~/.sane/ before attempting to scan.
then do

[root@abox ~]# lpstat -t
scheduler is running
system default destination: HP-ENVY_Randy
device for HP-ENVY_Randy: hp:/usb/ENVY_4500_series?serial=CN45H1420G05X4
HP-ENVY_Randy accepting requests since Wed 27 Nov 2019 10:21:03 PM EST
printer HP-ENVY_Randy is idle. enabled since Wed 27 Nov 2019 10:21:03 PM EST
--

1) Make sure the user is a member of the 'lp' group (for r/w access to USB-connected scanners).
Added me to lp group. Same results. (But then .. printer works now. Just no scanner function)
..

3) Try removing any existing ~/.sane/ before attempting to scan.
Same result.
..
[root@abox ~]# hp-scan
warning: hp-scan should not be run as root/superuser.

HP Linux Imaging and Printing System (ver. 3.19.10)
Scan Utility ver. 2.2

Copyright (c) 2001-18 HP Development Company, LP
This software comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to distribute it
under certain conditions. See COPYING file for more details.

warning: No destinations specified. Adding 'file' destination by default.
Using device hpaio:/usb/ENVY_4500_series?serial=CN45H1420G05X4
Opening connection to device...
error: SANE: Invalid argument (code=4)
[root@abox ~]#

I did a duckduckgo search on linux 'error: SANE: Invalid argument (code=4)' and there are a lot of useful suggestions. For example, this one.

https://cromwell-intl.com/open-sourc...-argument.html

There are more. Wor your way through it and see if it helps.

Heh. Great minds. I did the same. (same site). Results:

[root@abox ~]# lsusb
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 006: ID 046d:c077 Logitech, Inc. M105 Optical Mouse
Bus 001 Device 012: ID 03f0:c511 HP, Inc
Bus 001 Device 004: ID 05e3:0610 Genesys Logic, Inc. 4-port hub
Bus 001 Device 003: ID 04d9:1702 Holtek Semiconductor, Inc. Keyboard LKS02
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
[root@abox ~]#
[root@abox ~]# ls -l /dev/bus/usb/001
total 0
crw-rw-r-- 1 root root 189, 0 Nov 27 19:05 001
crw-rw-r-- 1 root root 189, 1 Nov 27 19:05 002
crw-rw-r-- 1 root root 189, 2 Nov 27 19:05 003
crw-rw-r-- 1 root root 189, 3 Nov 27 19:05 004
crw-rw-r-- 1 root root 189, 5 Nov 27 19:05 006
crw-rw-r--+ 1 root lp 189, 11 Nov 28 09:23 012
[root@abox ~]#
[root@abox ~]# getfacl /dev/bus/usb/001/012
getfacl: Removing leading '/' from absolute path names
# file: dev/bus/usb/001/012
# owner: root
# group: lp
user::rw-
user:randy:rw-
group::rw-
mask::rw-
other::r--

----------------------------------------------------
Cromwell has a "scanner" listed. I have only "lp". Since my printer IS my scanner, that sorta makes sense.
But, maybe sane is looking for "scanner"?

Two more commands (with which I was not previously aware):
-----------
randy@abox ~]$ scanimage -L
device `hpaio:/usb/ENVY_4500_series?serial=CN45H1420G05X4' is a Hewlett-Packard ENVY_4500_series all-in-one
[randy@abox ~]$ sane-find-scanner

# sane-find-scanner will now attempt to detect your scanner. If the
# result is different from what you expected, first make sure your
# scanner is powered up and properly connected to your computer.

# No SCSI scanners found. If you expected something different, make sure that
# you have loaded a kernel SCSI driver for your SCSI adapter.

could not open USB device 0x8087/0x0024 at 002:002: Access denied (insufficient permissions)
could not open USB device 0x1d6b/0x0002 at 002:001: Access denied (insufficient permissions)
could not open USB device 0x046d/0xc077 at 001:006: Access denied (insufficient permissions)
found USB scanner (vendor=0x03f0 [HP], product=0xc511 [ENVY 4500 series]) at libusb:001:012
could not open USB device 0x05e3/0x0610 at 001:004: Access denied (insufficient permissions)
could not open USB device 0x04d9/0x1702 at 001:003: Access denied (insufficient permissions)
could not open USB device 0x8087/0x0024 at 001:002: Access denied (insufficient permissions)
could not open USB device 0x1d6b/0x0002 at 001:001: Access denied (insufficient permissions)
# Your USB scanner was (probably) detected. It may or may not be supported by
# SANE. Try scanimage -L and read the backend's manpage.

# Not checking for parallel port scanners.

# Most Scanners connected to the parallel port or other proprietary ports
# can't be detected by this program.

# You may want to run this program as root to find all devices. Once you
# found the scanner devices, be sure to adjust access permissions as
# necessary.
[randy@abox ~]$