Network scanning fails (but printing OK) on HP M1217nfw

I recently tried to set up my HP M1217nfw for network printing and scanning on my LAN. I previously had it set up for USB printing and scanning, so I know both functions work via USB. As a network printer, the M1217nft works fine. But scanning does not work at all. Selecting "scan" from the device manager pops the xsane "scanning for devices" window, and then nothing for roughly a minute, when I get a dialog saying:
Failed to open device 'hpaio:/net/HP_LaserJet_Professional_M1217nfw_MFP?ip=192.168.1.205': Error during device I/O.

I also get the following error in /var/log/syslog:
Nov 16 21:09:13 owner python: io/hpmud/hpmud.c 223: invalid channel_open state, current io_mode=raw/uni service=HP-MESSAGE hp:/net/HP_LaserJet_Professional_M1217nfw_MFP?ip=192.168.1.205
Nov 16 21:09:13 owner python: io/hpmud/hpmud.c 636: invalid channel_close state
Nov 16 21:29:16 owner xsane: io/hpmud/jd.c 645: timeout read_channel sec=45 hp:/net/HP_LaserJet_Professional_M1217nfw_MFP?ip=192.168.1.205
Nov 16 21:29:16 owner xsane: bb_marvell.c 346: invalid get_msg tmo=45 total=0 uri=hp:/net/HP_LaserJet_Professional_M1217nfw_MFP?ip=192.168.1.205

Output of hp-check
Saving output in log file: /home/owner/hp-check.log

HP Linux Imaging and Printing System (ver. 3.13.11)
Dependency/Version Check Utility ver. 15.1

Copyright (c) 2001-13 Hewlett-Packard 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.

Note: hp-check can be run in three modes:
1. Compile-time check mode (-c or --compile): Use this mode before compiling the HPLIP supplied tarball (.tar.gz or .run) to determine if the proper dependencies are installed to successfully compile
HPLIP.
2. Run-time check mode (-r or --run): Use this mode to determine if a distro supplied package (.deb, .rpm, etc) or an already built HPLIP supplied tarball has the proper dependencies installed to
successfully run.
3. Both compile- and run-time check mode (-b or --both) (Default): This mode will check both of the above cases (both compile- and run-time dependencies).

Check types:
a. EXTERNALDEP - External Dependencies
b. GENERALDEP - General Dependencies (required both at compile and run time)
c. COMPILEDEP - Compile time Dependencies
d. [All are run-time checks]
PYEXT SCANCONF QUEUES PERMISSION

Status Types:
    OK
    MISSING - Missing Dependency or Permission or Plug-in
    INCOMPAT - Incompatible dependency-version or Plugin-version

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

 Kernel: 3.5.0-43-generic #66-Ubuntu SMP Wed Oct 23 12:01:49 UTC 2013 GNU/Linux
 Host: owner
 Proc: 3.5.0-43-generic #66-Ubuntu SMP Wed Oct 23 12:01:49 UTC 2013 GNU/Linux
 Distribution: ubuntu 12.10
 Bitness: 64 bit

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

HPLIP-Version: HPLIP 3.13.11
HPLIP-Home: /usr/share/hplip
HPLIP-Installation: Auto installation is supported for ubuntu distro 12.10 version

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

[hplip]
version=3.13.11

[dirs]
home=/usr/share/hplip
run=/var/run
ppd=/usr/share/ppd/HP
ppdbase=/usr/share/ppd
doc=/usr/share/doc/hplip-3.13.11
html=/usr/share/doc/hplip-3.13.11
icon=/usr/share/applications
cupsbackend=/usr/lib/cups/backend
cupsfilter=/usr/lib/cups/filter
drv=/usr/share/cups/drv/hp
bin=/usr/bin

# 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=3.13.11
restricted-build=no
ui-toolkit=qt4
qt3=no
qt4=yes
policy-kit=no
lite-build=no
udev-acl-rules=yes
udev_sysfs_rules=no
hpcups-only-build=no
hpijs-only-build=no

Current contents of '/var/lib/hp/hplip.state' file:
[plugin]
installed = 1
eula = 1
version = 3.13.11

Current contents of '~/.hplip/hplip.conf' file:
[upgrade]
notify_upgrade = true
last_upgraded_time = 1384617028
pending_upgrade_time = 0
latest_available_version = 3.13.11

[settings]
systray_visible = 0
systray_messages = 0

[last_used]
device_uri = "hp:/net/HP_LaserJet_Professional_M1217nfw_MFP?ip=192.168.1.205"
printer_name = HP_LaserJet_Professional_M1217nfw_MFP
working_dir = .

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

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

[polling]
enable = false
interval = 5
device_list =

[fax]
voice_phone =
email_address =

[installation]
date_time = 11/16/2013 21:32:47
version = 3.13.11

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

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

 policykit Admin-Policy-framework OPTIONAL - 0.104 OK -
 gs Ghostscript REQUIRED 7.05 9.06 OK -
 network Network-wget OPTIONAL - 1.13.4 OK -
 scanimage Shell-Scanning OPTIONAL 1.0 1.0.23 OK -
 avahi-utils avahi-utils OPTIONAL - 0.6.31 OK -
 dbus DBus REQUIRED - 1.6.4 OK -
 cups CUPS REQUIRED 1.1 1.6.1 OK 'CUPS Scheduler is running'
 xsane SANE-GUI OPTIONAL 0.9 0.998 OK -

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

 reportlab Python-PDF-Lib OPTIONAL 2.0 2.5 OK -
 libcrypto OpenSSL-Crypto-Lib REQUIRED - 1.0.1 OK -
 pil Python-Image-Lib OPTIONAL - 1.1.7 OK -
 pyqt4-dbus PyQt4-DBUS REQUIRED 4.0 4.9.3 OK -
 libjpeg JPEG-Lib REQUIRED - - OK -
 libpthread POSIX-Threads-Lib REQUIRED - 2.15 OK -
 python-dbus Python-DBUS REQUIRED 0.80.0 1.1.1 OK -
 python-devel Python-SDK REQUIRED 2.2 2.7.3 OK -
 pyqt4 Python-Qt4 REQUIRED 4.0 4.9.3 OK -
 cups-devel CUPS-SDK REQUIRED - 1.6.1 OK -
 sane-devel SANE-SDK REQUIRED - 1.0.23 OK -
 libusb USB-Lib REQUIRED - 1.0 OK -
 sane Scan-Lib REQUIRED - 1.0.23 OK -
 cups-image CUPS-Image-Lib REQUIRED - 1.6.1 OK -
 libnetsnmp-devel SNMP-Networking-SDK REQUIRED 5.0.9 5.4.3 OK -
 python-xml Python-XML-Lib REQUIRED - 2.1.0 OK -
 python-notify Desktop-notifications OPTIONAL - - OK -

------------------------------
| Compile Time Dependencies |
------------------------------

 gcc gcc-Compiler REQUIRED - 4.7.2 OK -
 libtool Build-tools REQUIRED - 2.4.2 OK -
 make GNU-Build-tools REQUIRED 3.0 3.81 OK -

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

 cupsext CUPS-Extension REQUIRED - 3.13.11 OK -
 pcardext PhotoCard-Extension REQUIRED - 3.13.11 OK -
 hpmudext IO-Extension REQUIRED - 3.13.11 OK -

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

 hpaio HPLIP-SANE-Backend REQUIRED - 3.13.11 OK 'hpaio found in /etc/sane.d/dll.conf'
 scanext Scan-SANE-Extension REQUIRED - 3.13.11 OK -

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

device `hpaio:/net/HP_LaserJet_Professional_M1217nfw_MFP?ip=192.168.1.205' is a Hewlett-Packard HP_LaserJet_Professional_M1217nfw_MFP all-in-one

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

No devices found.

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

HP_LaserJet_Professional_M1217nfw_MFP
-------------------------------------
Type: Printer
Device URI: hp:/net/HP_LaserJet_Professional_M1217nfw_MFP?ip=192.168.1.205
PPD: /etc/cups/ppd/HP_LaserJet_Professional_M1217nfw_MFP.ppd
PPD Description: HP LaserJet Professional m1217nfw MFP, hpcups 3.13.11, requires proprietary plugin
Printer ready to printr HP_LaserJet_Professional_M1217nfw_MFP is idle. enabled since Sat 16 Nov 2013 09:09:24 PM EST
Required plug-in status: Installed
Communication status: Good

HP_LaserJet_Professional_M1217nfw_MFP_fax
-----------------------------------------
Type: Fax
Device URI: hpfax:/net/HP_LaserJet_Professional_M1217nfw_MFP?ip=192.168.1.205
PPD: /etc/cups/ppd/HP_LaserJet_Professional_M1217nfw_MFP_fax.ppd
PPD Description: HP Fax3 hpcups
Printer status: printer HP_LaserJet_Professional_M1217nfw_MFP_fax is idle. enabled since Sat 16 Nov 2013 08:49:21 PM EST
Required plug-in status: Installed
Communication status: Good

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

No errors or warnings.

Done.