After upgrading from V12.04 to V14.04 I am not able to print. I am using an HP LaserJet 400 M451dn. The printer troubleshooter told me that there is no solution to the problem.

This is the output of the advanced diagnositc output. (Due to limited space I cut the output!) Can anybody tell me what is going wrong. I am using the printer via USB ?

Page 1 (Scheduler not running?): {'cups_connection_failure': False} Page 2 (Is local server publishing?): {'local_server_exporting_printers': False} Page 3 (Choose printer): {'cups_dest': , 'cups_instance': None, 'cups_queue': u'HP-LaserJet-400-color-M451dn', 'cups_queue_listed': True} Page 4 (Check printer sanity): {'cups_device_uri_scheme': u'hp', 'cups_printer_dict': {'device-uri': u'hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670', 'printer-info': u'Hewlett-Packard HP LaserJet 400 color M451dn', 'printer-is-shared': True, 'printer-location': u'Pinatubo', 'printer-make-and-model': u'HP LJ 300-400 color M351-M451 Postscript (recommended)', 'printer-state': 4, 'printer-state-message': u'', 'printer-state-reasons': [u'none'], 'printer-type': 8556636, 'printer-uri-supported': u'ipp://localhost:631/printers/HP-LaserJet-400-color-M451dn'}, 'cups_printer_remote': False, 'hplip_output': (['', '\x1b[01mHP Linux Imaging and Printing System (ver. 3.14.6)\x1b[0m', '\x1b[01mDevice Information Utility ver. 5.2\x1b[0m', '', '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.', '', '', '\x1b[01mhp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670\x1b[0m', '', '\x1b[01mDevice Parameters (dynamic data):\x1b[0m', '\x1b[01m Parameter Value(s) \x1b[0m', ' ---------------------------- ----------------------------------------------------------', ' back-end hp ', " cups-printers ['HP-LaserJet-400-color-M451dn'] ", ' cups-uri hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670 ', ' dev-file ', ' device-state -1 ', ' device-uri hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670 ', ' deviceid ', ' error-state 101 ', ' host ', ' is-hp True ', ' panel 0 ', ' panel-line1 ', ' panel-line2 ', ' port 1 ', ' serial CNFF308670 ', ' status-code 5002 ', ' status-desc ', '\x1b[01m', 'Model Parameters (static data):\x1b[0m', '\x1b[01m Parameter Value(s) \x1b[0m', ' ---------------------------- ----------------------------------------------------------', ' align-type 0 ', ' clean-type 0 ', ' color-cal-type 0 ', ' copy-type 0 ', ' embedded-server-type 0 ', ' fax-type 0 ', ' fw-download False ', ' icon hp_color_laserjet_cp2025.png ', ' io-mfp-mode 1 ', ' io-mode 1 ', ' io-support 6 ', ' job-storage 0 ', ' linefeed-cal-type 0 ', ' model HP_LaserJet_400_color_M451dn ', ' model-ui HP LaserJet 400 Color m451dn ', ' model1 HP LaserJet 400 Color M451dn ', ' monitor-type 0 ', ' panel-check-type 0 ', ' pcard-type 0 ', ' plugin 0 ', ' plugin-reason 0 ', ' power-settings 0 ', ' ppd-name lj_300_400_color_m351_m451 ', ' pq-diag-type 0 ', ' r-type 0 ', ' r0-agent1-kind 4 ', ' r0-agent1-sku CE410A/CE410X ', ' r0-agent1-type 1 ', ' r0-agent2-kind 4 ', ' r0-agent2-sku CE411A ', ' r0-agent2-type 4 ', ' r0-agent3-kind 4 ', ' r0-agent3-sku CE413A ', ' r0-agent3-type 5 ', ' r0-agent4-kind 4 ', ' r0-agent4-sku CE412A ', ' r0-agent4-type 6 ', ' scan-src 0 ', ' scan-type 0 ', ' status-battery-check 0 ', ' status-dynamic-counters 0 ', ' status-type 3 ', ' support-released True ', ' support-subtype 2202411 ', ' support-type 2 ', ' support-ver 3.12.2 ', " tech-class ['Postscript'] ", " tech-subclass ['Normal'] ", ' tech-type 4 ', ' usb-pid 3882 ', ' usb-vid 1008 ', ' wifi-config 0 ', '\x1b[01m', 'Status History (most recent first):\x1b[0m', '\x1b[01m Date/Time Code Status Description User Job ID \x1b[0m', ' -------------------- ----- ---------------------------------------- -------- --------', ' 08/21/14 00:07:25 5012 Device communication error richard 0 ', ' 08/20/14 13:42:44 500 Started a print job richard 4214 ', '', '', 'Done.', ''], ['\x1b[35;01mwarning: No display found.\x1b[0m', '\x1b[31;01merror: hp-info -u/--gui requires Qt4 GUI support. Entering interactive mode.\x1b[0m', '\x1b[31;01merror: Unable to communicate with device (code=12): hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670\x1b[0m', '\x1b[31;01merror: Error opening device (Device not found).\x1b[0m', ''], 0), 'is_cups_class': False, 'local_cups_queue_attributes': {'charset-configured': u'utf-8', 'charset-supported': [u'us-ascii', u'utf-8'], 'color-supported': True, 'compression-supported': [u'none', u'gzip'], 'copies-default': 1, 'copies-supported': (1, 9999), 'cups-version': u'1.7.2', 'device-uri': u'hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670', 'document-format-default': u'application/octet-stream', 'document-format-supported': [u'application/octet-stream', u'application/pdf', u'application/postscript', u'application/vnd.adobe-reader-postscript', u'application/vnd.cups-command', u'application/vnd.cups-pdf', u'application/vnd.cups-pdf-banner', u'application/vnd.cups-postscript', u'application/vnd.cups-raw', u'application/vnd.samsung-ps', u'application/x-cshell', u'application/x-csource', u'application/x-perl', u'application/x-shell', u'image/gif', u'image/jpeg', u'image/png', u'image/tiff', u'image/urf', u'image/x-bitmap', u'image/x-photocd', u'image/x-portable-anymap', u'image/x-portable-bitmap', u'image/x-portable-graymap', u'image/x-portable-pixmap', u'image/x-sgi-rgb', u'image/x-sun-raster', u'image/x-xbitmap', u'image/x-xpixmap', u'image/x-xwindowdump', u'text/css', u'text/html', u'text/plain'], 'finishings-default': 3, 'finishings-supported': [3], 'generated-natural-language-supported': [u'en-us'], 'ipp-versions-supported': [u'1.0', u'1.1', u'2.0', u'2.1'], 'ippget-event-life': 15, 'job-creation-attributes-supported': [u'copies', u'finishings', u'ipp-attribute-fidelity', u'job-hold-until', u'job-name', u'job-priority', u'job-sheets', u'media', u'media-col', u'multiple-document-handling', u'number-up', u'output-bin', u'orientation-requested', u'page-ranges', u'print-color-mode', u'print-quality', u'printer-resolution', u'sides'], 'job-hold-until-default': u'no-hold', 'job-hold-until-supported': [u'no-hold', u'indefinite', u'day-time', u'evening', u'night', u'second-shift', u'third-shift', u'weekend'], 'job-ids-supported': True, 'job-k-limit': 0, 'job-k-octets-supported': (0, 470914416), 'job-page-limit': 0, 'job-priority-default': 50, 'job-priority-supported': [100], 'job-quota-period': 0, 'job-settable-attributes-supported': [u'copies', u'finishings', u'job-hold-until', u'job-name', u'job-priority', u'media', u'media-col', u'multiple-document-handling', u'number-up', u'output-bin', u'orientation-requested', u'page-ranges', u'print-color-mode', u'print-quality', u'printer-resolution', u'sides'], 'job-sheets-default': (u'none', u'none'), 'job-sheets-supported': [u'none', u'classified', u'confidential', u'form', u'secret', u'standard', u'topsecret', u'unclassified'], 'jpeg-k-octets-supported': (0, 470914416), 'jpeg-x-dimension-supported': (0, 65535), 'jpeg-y-dimension-supported': (1, 65535), 'marker-change-time': 0, 'media-bottom-margin-supported': [423], 'media-col-default': u'(unknown IPP value tag 0x34)', 'media-col-supported': [u'media-bottom-margin', u'media-left-margin', u'media-right-margin', u'media-size', u'media-source', u'media-top-margin', u'media-type'], 'media-default': u'iso_a4_210x297mm', 'media-left-margin-supported': [423], 'media-right-margin-supported': [423],