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- Run lsusb. Example:
Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 008 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 008: ID 046d:c713 Logitech, Inc.
Bus 001 Device 009: ID 046d:c714 Logitech, Inc.
Bus 001 Device 006: ID 046d:0b04 Logitech, Inc.
Bus 001 Device 005: ID 046d:c51a Logitech, Inc. MX Revolution/G7 Cordless Mouse
Bus 001 Device 007: ID 05e3:0608 Genesys Logic, Inc. USB-2.0 4-Port HUB
Bus 001 Device 003: ID 04b8:084a Seiko Epson Corp.
Bus 001 Device 002: ID 050d:0416 Belkin Components
Bus 001 Device 004: ID 05e3:0608 Genesys Logic, Inc. USB-2.0 4-Port HUB
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
- Bus 001 Device 003 ID 04b8 is the printer identifier.
- Run: ls -l /dev/bus/usb/001 -> This looks for usb devices attached to bus 001.
total 0
crw-rw-r-- 1 root usb 189, 0 Feb 8 20:56 001
crw-rw-r-- 1 root usb 189, 1 Feb 8 20:56 002
crw-rw-r-- 1 root scanner 189, 2 Feb 9 05:50 003
crw-rw-r-- 1 root usb 189, 3 Feb 8 20:56 004
crw-rw-r-- 1 root usb 189, 4 Feb 8 20:56 005
crw-rw-r-- 1 root usb 189, 5 Feb 8 20:56 006
crw-rw-r-- 1 root usb 189, 6 Feb 8 20:56 007
crw-rw-r-- 1 root usb 189, 7 Feb 8 20:56 008
crw-rw-r-- 1 root usb 189, 8 Feb 8 20:56 009
- Change dir to /etc/udev/rules.d -> Look for the udev rule that assigned the printer to the 'scanner' group. This rule should contain the '04b8' identifier.
- Copy and edit to create a rule file to assign the printer to the 'lp' group -> 10-cups-usb.rules:
#Stylus NX400
ATTRS{idVendor}=="04b8", ATTRS{idProduct}=="084a", MODE:="0660", GROUP:="lp", ENV{libsane_matched}:="yes"
- Changed the assignment operators from '=' to ':=' as the line above has the three instances. According to the udev documentation, this prevents the assignment from being overridden by higher-numbered rule files. This is the only line in the new .rules file.
- Run: ls -l /dev/bus/usb/001 again:
total 0
crw-rw-r-- 1 root usb 189, 0 Feb 8 20:56 001
crw-rw-r-- 1 root usb 189, 1 Feb 8 20:56 002
crw-rw-r-- 1 root usb 189, 3 Feb 8 20:56 004
crw-rw-r-- 1 root usb 189, 4 Feb 8 20:56 005
crw-rw-r-- 1 root usb 189, 5 Feb 8 20:56 006
crw-rw-r-- 1 root usb 189, 6 Feb 8 20:56 007
crw-rw-r-- 1 root usb 189, 7 Feb 8 20:56 008
crw-rw-r-- 1 root usb 189, 8 Feb 8 20:56 009
crw-rw----+ 1 root lp 189, 9 Feb 9 22:07 010
- Check for 'lp'. This should indicate the printer is assigned to the 'lp' group. Disconnect and reconnect the printer. Then in web browser run: localhost:631 . Add printer. Verify if the printer is available in usb. Example:
Description: EPSON Stylus NX400
Location:
Driver: Epson Stylus NX400 - CUPS+Gutenprint v5.2.4 (color)
Connection: usb://EPSON/Stylus%20NX400?serial=4B4E5 ... nterface=1
- Print test page.
- May need to run: gpasswd <user> lp . This add <user> to the 'lp' group.
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The gpasswd command was not needed this time. But may be for others who may run into a similar problem. Apparently udev assigned this multifunction printer to the 'scanner' group and CUPS does not see it. May be CUPS does not have a problem with a printer-only USB type printer. Now NX400 works under CUPS and its scanner works under iscan.

Hope this help some people, if not with the NX400, then perhaps with similar printers. Hate to say it but this should not have taken hours to investigate and remedied. Things like this make me reluctant to recommend Linux to anyone.
