Unable to write print data: Input/output error ??

[Clément Danjou]

Hi,
Since last evening, I can't print anything on my Canon Pixma MP520 after a reboot. It starts to print, and stop to 10%, and 5 minutes after my printer eject the paper.
In fact, I had many issues before, with the same error, but, I don't know exactly how, I succeed to print. I thought it's an authentification issue, maybe I was logged as root for cups so it let met print until the next reboot ?
This morning, I tried to print, I have just two errors:

E [29/Nov/2009:12:33:59 +0100] Returning IPP client-error-not-authorized for Print-Job (ipp://localhost:631/printers/Canon_MP520_series) from localhost
E [29/Nov/2009:12:34:13 +0100] [Job 226] Unable to write print data: Input/output error

Then, I change my printers.conf from:
  <Limit Send-Document Send-URI Hold-Job Release-Job Restart-Job Purge-Jobs Set-Job-Attributes Create-Job-Subscription Renew-Subscription Cancel-Subscription Get-Notifications Reprocess-Job Cancel-Current-Job Suspend-Current-Job Resume-Job CUPS-Move-Job CUPS-Get-Document>
    Require user @OWNER @SYSTEM
    Order deny,allow
  </Limit>

To:

  <Limit Send-Document Send-URI Hold-Job Release-Job Restart-Job Purge-Jobs Set-Job-Attributes Create-Job-Subscription Renew-Subscription Cancel-Subscription Get-Notifications Reprocess-Job Cancel-Current-Job Suspend-Current-Job Resume-Job CUPS-Move-Job CUPS-Get-Document>
    Require user
    Order deny,allow
  </Limit>

Then, I have just:
Unable to write print data: Input/output error

This is my configuration:
-Default conf for printers.conf
-Creating a 40-basic-permissions.rules:
#USB devices (usbfs replacement)
SUBSYSTEM=="usb", ENV{DEVTYPE}=="usb_device", MODE="0666"
SUBSYSTEM=="usb_device",                MODE="0666"
-My user is in lp and lpadmin group
-I have privilege for printers in Ubuntu users manager
-Informations:
Description:	Canon MP520 series
Location:	Local Printer
Driver:	Canon PIXMA MP520 - CUPS+Gutenprint v5.2.4 (color, 2-sided printing)
Connection:	usb://Canon/MP520%20series
Defaults:	job-sheets=none, none media=iso_a4_210x297mm sides=one-sided

Tried to change:
Connection:	file:/dev/usb/usblp0

=> Same issue

Any idea ? I'm a little bit desperate.

And excuse my english.