我的佳能 MX870 在 11.10 中安装得很好，但自从升级到 12.04 后，它就不再工作了。打印机在打印设置中被识别，当我尝试打印测试页时，打印机 LCD 显示“正在处理”消息，但随后消失并且没有任何反应。这是我的日志（请注意，尽管访问日志显示成功，但打印并未成功）：
# /var/log/cups/access_log
localhost - - [22/May/2012:12:29:35 -0400] "POST /printers/Canon-MX870 HTTP/1.1" 200 412 Print-Job successful-ok
——
# /var/log/cups/error_log
W [22/May/2012:12:25:51 -0400] failed to CreateProfile: org.freedesktop.ColorManager.AlreadyExists:profile id 'Canon-MX870-Gray..' already exists
W [22/May/2012:12:25:51 -0400] failed to CreateProfile: org.freedesktop.ColorManager.AlreadyExists:profile id 'Canon-MX870-RGB..' already exists
W [22/May/2012:12:25:51 -0400] failed to CreateDevice: org.freedesktop.ColorManager.AlreadyExists:device id 'cups-Canon-MX870' already exists
W [22/May/2012:12:25:51 -0400] failed to CreateProfile: org.freedesktop.ColorManager.AlreadyExists:profile id 'Canon-MX870-Gray..' already exists
W [22/May/2012:12:25:51 -0400] failed to CreateProfile: org.freedesktop.ColorManager.AlreadyExists:profile id 'Canon-MX870-RGB..' already …