Warning of HPLIP Status Service

I did the following operation:
superkey > startup application > uncheck HP System Tray Service
Restarted the system.
still the error persists.
Simple Scan is not working

I also Diagnosed HPLIP Driver through HP Device Manager. The outpot was as under:
------------O U T P UT ---------------------------

HP Linux Imaging and Printing System (ver. 3.18.4)
Self Diagnse Utility and Healing Utility ver. 1.0

Copyright (c) 2001-15 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.

HP Linux Imaging and Printing System (ver. 3.18.4)
Self Diagnse Utility and Healing Utility ver. 1.0

Copyright (c) 2001-15 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.

/Gtk-Message: 17:06:52.428: Failed to load module "canberra-gtk-module"
-Gtk-Message: 17:06:52.456: Failed to load module "canberra-gtk-module"

Checking for Deprecated items....
No Deprecated items are found

Checking for HPLIP updates....

HP Linux Imaging and Printing System (ver. 3.18.4)
HPLIP upgrade latest version ver. 1.0

Copyright (c) 2001-15 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.

Latest version of HPLIP is already installed.

Checking for Dependencies....

---------------
| SYSTEM INFO |
---------------

 Kernel: 4.15.0-55-generic #60-Ubuntu SMP Tue Jul 2 18:22:20 UTC 2019 GNU/Linux
 Host: linux
 Proc: 4.15.0-55-generic #60-Ubuntu SMP Tue Jul 2 18:22:20 UTC 2019 GNU/Linux
 Distribution: 12 18.04
 Bitness: 64 bit

-----------------------
| HPLIP CONFIGURATION |
-----------------------

HPLIP-Version: HPLIP 3.18.4
HPLIP-Home: /usr/share/hplip
HPLIP-Installation: Auto installation is supported for ubuntu distro 18.04 version

Current contents of '/etc/hp/hplip.conf' file:
# hplip.conf. Generated from hplip.conf.in by configure.

[hplip]
version=3.18.4

[dirs]
home=/usr/share/hplip
run=/var/run
ppd=/usr/share/ppd/HP
ppdbase=/usr/share/ppd
doc=/usr/share/doc/hplip-3.18.4
html=/usr/share/doc/hplip-3.18.4
icon=/usr/share/applications
cupsbackend=/usr/lib/cups/backend
cupsfilter=/usr/lib/cups/filter
drv=/usr/share/cups/drv/hp
bin=/usr/bin
apparmor=/etc/apparmor.d
# Following values are determined at configure time and cannot be changed.
[configure]
network-build=yes
libusb01-build=no
pp-build=no
gui-build=yes
scanner-build=yes
fax-build=yes
dbus-build=yes
cups11-build=no
doc-build=yes
shadow-build=no
hpijs-install=no
foomatic-drv-install=no
foomatic-ppd-install=no
foomatic-rip-hplip-install=no
hpcups-install=yes
cups-drv-install=yes
cups-ppd-install=no
internal-tag=3.18.4
restricted-build=no
ui-toolkit=qt4
qt3=no
qt4=yes
qt5=no
policy-kit=no
lite-build=no
udev_sysfs_rules=no
hpcups-only-build=no
hpijs-only-build=no
apparmor_build=yes
class-driver=no

Current contents of '/var/lib/hp/hplip.state' file:
[plugin]
installed = 1
eula = 1
version = 3.18.4

Current contents of '~/.hplip/hplip.conf' file:
[upgrade]
notify_upgrade = true
last_upgraded_time = 1550052235
pending_upgrade_time = 0
latest_available_version = 3.17.10

[settings]
systray_visible = 0
systray_messages = 0

[last_used]
device_uri = "hp:/usb/HP_LaserJet_M1005?serial=KJ19KXY"
printer_name =
working_dir = .

[commands]
scan = /usr/bin/xsane -V %SANE_URI%

[refresh]
rate = 30
enable = true
type = 1

[polling]
enable = false
interval = 5
device_list =

[fax]
voice_phone =
email_address =

[installation]
date_time = Saturday 27 July 2019 17:06:53
version = 3.18.4

 <Package-name> <Package-Desc> <Required/Optional> <Min-Version> <Installed-Version> <Status> <Comment>

--------------
| COMPILEDEP |
--------------

 gcc gcc - GNU Project C and C++ Compiler REQUIRED - 7.4.0 OK -
 make make - GNU make utility to maintain groups of programs REQUIRED 3.0 4.1 OK -
 libtool libtool - Library building support services REQUIRED - 2.4.6 OK -

------------------------
| General Dependencies |
------------------------

 libcrypto libcrypto - OpenSSL cryptographic library REQUIRED - 1.1.1 OK -
 python-xml Python XML libraries REQUIRED - 2.2.5 OK -
 libnetsnmp-devel libnetsnmp-devel - SNMP networking library development files REQUIRED 5.0.9 5.7.3 OK -
 sane-devel SANE - Scanning library development files REQUIRED - - OK -
 pil PIL - Python Imaging Library (required for commandline scanning with hp-scan) OPTIONAL - 1.1.7 OK -
 pyqt4-dbus PyQt 4 DBus - DBus Support for PyQt4 REQUIRED 4.0 4.12.1 OK -
 libpthread libpthread - POSIX threads library REQUIRED - 2.27 OK -
 python-devel Python devel - Python development files REQUIRED 2.2 2.7.15 OK -
 cups-devel CUPS devel- Common Unix Printing System development files REQUIRED - 2.2.7 OK -
 python-dbus Python DBus - Python bindings for DBus REQUIRED 0.80.0 1.2.6 OK -
 cups-ddk CUPS DDK - CUPS driver development kit OPTIONAL - - OK -
 reportlab Reportlab - PDF library for Python OPTIONAL 2.0 3.4.0 OK -
 pyqt4 PyQt 4- Qt interface for Python (for Qt version 4.x) REQUIRED 4.0 4.12.1 OK -
 libusb libusb - USB library REQUIRED - 1.0 OK -
 cups-image CUPS image - CUPS image development files REQUIRED - 2.2.7 OK -
 python2X Python 2.2 or greater - Python programming language REQUIRED 2.2 2.7.15 OK -
 python-notify Python libnotify - Python bindings for the libnotify Desktop notifications OPTIONAL - - OK -
 libjpeg libjpeg - JPEG library REQUIRED - - OK -
 sane SANE - Scanning library REQUIRED - - OK -

----------------------
| Scan Configuration |
----------------------

 scanext Scan-SANE-Extension REQUIRED - 3.18.4 OK -
 hpaio HPLIP-SANE-Backend REQUIRED - 3.18.4 OK 'hpaio found in /etc/sane.d/dll.conf'

-------------------------
| External Dependencies |
-------------------------

 gs GhostScript - PostScript and PDF language interpreter and previewer REQUIRED 7.05 9.26 OK -
 scanimage scanimage - Shell scanning program OPTIONAL 1.0 1.0.27 OK -
 cups CUPS - Common Unix Printing System REQUIRED 1.1 2.2.7 OK 'CUPS Scheduler is running'
 network network -wget OPTIONAL - 1.19.4 OK -
 policykit PolicyKit - Administrative policy framework OPTIONAL - 0.105 OK -
Gtk-Message: 17:07:00.747: Failed to load module "canberra-gtk-module"
Gtk-Message: 17:07:00.774: Failed to load module "canberra-gtk-module"
 xsane xsane - Graphical scanner frontend for SANE OPTIONAL 0.9 0.999 OK -
 dbus DBus - Message bus system REQUIRED - 1.12.2 OK -
 avahi-utils avahi-utils OPTIONAL - 0.7 OK -

---------------------
| Python Extentions |
---------------------

 hpmudext IO-Extension REQUIRED - 3.18.4 OK -
 cupsext CUPS-Extension REQUIRED - 3.18.4 OK -

------------------------------
| DISCOVERED SCANNER DEVICES |
------------------------------

device `hpaio:/usb/HP_LaserJet_M1005?serial=KJ19KXY' is a Hewlett-Packard HP_LaserJet_M1005 all-in-one
device `hpljm1005:libusb:004:005' is a Hewlett-Packard LaserJet M1005 multi-function peripheral

--------------------------
| DISCOVERED USB DEVICES |
--------------------------

  Device URI Model
  -------------------------------- -----------------
  hp:/usb/HP_LaserJet_M1005?serial HP LaserJet M1005
  =KJ19KXY

---------------------------------
| INSTALLED CUPS PRINTER QUEUES |
---------------------------------

HP-LaserJet-M1005
-----------------
Type: Printer
Device URI: hp:/usb/HP_LaserJet_M1005?serial=KJ19KXY
PPD: /etc/cups/ppd/HP-LaserJet-M1005.ppd
warning: Failed to read /etc/cups/ppd/HP-LaserJet-M1005.ppd ppd file
PPD Description:
Printer status: printer HP-LaserJet-M1005 is idle. enabled since Thursday 21 February 2019 04:39:05 PM IST
Required plug-in status: Installed
Communication status: Good

--------------
| PERMISSION |
--------------

USB HP-LaserJet-M1005 Required - - OK Node:'/dev/bus/usb/004/005' Perm:' root lp rw- rw- rw- rw- r--'

Checking for Configured Queues....
warning: Fail to read ppd=/etc/cups/ppd/HP-LaserJet-M1005.ppd file
warning: Insufficient permission to access file /etc/cups/ppd/HP-LaserJet-M1005.ppd
warning: Could not complete Queue(s) configuration check

Checking for HP Properitery Plugin's....
Plugin's already installed

Diagnose completed...

More information on Troubleshooting,How-To's and Support is available on http://hplipopensource.com/hplip-web/index.html

Please close this terminal manually.

---------------------- E N D ------------------------------------

warning: Fail to read ppd=/etc/cups/ppd/HP-LaserJet-M1005.ppd file
warning: Insufficient permission to access file /etc/cups/ppd/HP-LaserJet-M1005.ppd
warning: Could not complete Queue(s) configuration check

You seem not to have the authorization to print, because you are (probably) not member of the related user group.
What is the output of the command

groups

It is as under:

navin@linux:~$ groups
navin adm cdrom sudo dip plugdev lpadmin sambashare vboxusers
navin@linux:~$

You are not member of the lp (printer users) group, just lpadmin (printer admins).

Issue the command

sudo usermod -a -G lp navin

then log off and log again.

And the propsed action to cope with the warning
Gtk-Message: ... Failed to load module "canberra-gtk-module"
is the command

sudo apt install libcanberra-gtk-module

Applied the First Stuff:

--------------------------------------------
navin@linux:~$ sudo usermod -a -G lp navin
[sudo] password for navin:
navin@linux:~$
-------------------------------------------
Then Logged-Off
Re-Logged
Didn't got any warning.

Also Re-started the machine.
Warning of HPLIP Status Service appears as usual

Then applied the Second Stuff:

------------------------------------------
navin@linux:~$ sudo apt install libcanberra-gtk-module
Reading package lists... Done
Building dependency tree
Reading state information... Done
libcanberra-gtk-module is already the newest version (0.30-5ubuntu1).
The following package was automatically installed and is no longer required:
  gimp-help-common
Use 'sudo apt autoremove' to remove it.
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
navin@linux:~$
------------------------------------------

The problem persists.
Unable to scan even through Simple Scan

further guidance & help requested.

For the "No system tray detected on this system." message see some proposed workarounds in
https://askubuntu.com/questions/101828/no-system-tray-detected-on-this-system

And for the Canberra warning message you yould also try
sudo apt install libcanberra-gtk3-module

Finally i uninstalled the HPLIP.
I installed XSane and it is working fine now. It seems very good scanning programme.