我以前可以通过网络打印，但有一天我收到了此消息：
/usr/lib/cups/backend/lpd failed
这是我自己通过管理>打印（Lucid 10.04 Gnome UI）。
从外壳上看，它看起来不错：
$ lpq
Xerox is ready
no entries
以下是错误日志的最后几行：
$ cat /var/log/cups/error_log
D [28/Feb/2013:14:07:11 -0800] [Job 472] STATE: +connecting-to-device
D [28/Feb/2013:14:07:11 -0800] [Job 472] Looking up "cups-server.linfield.edu"...`
D [28/Feb/2013:14:07:11 -0800] [Job 472] Connecting to cups-server.linfield.edu:515 for printer
D [28/Feb/2013:14:07:11 -0800] [Job 472] Connecting to printer...
D [28/Feb/2013:14:07:11 -0800] [Job 472] STATE: -connecting-to-device
D [28/Feb/2013:14:07:11 -0800] [Job 472] Connected to printer...
D [28/Feb/2013:14:07:11 -0800] [Job 472] Connected to 10.171.255.15:515 (IPv4) (local port 1023)...
D [28/Feb/2013:14:07:11 -0800] [Job 472] lpd_command 02
D [28/Feb/2013:14:07:11 -0800] [Job 472] Sending command string (2 bytes)...
D [28/Feb/2013:14:07:11 -0800] [Job 472] Reading command status...
D [28/Feb/2013:14:07:11 -0800] [Job 472] lpd_command returning 1
D [28/Feb/2013:14:07:11 -0800] [Job 472] Backend returned status 1 (failed)
D [28/Feb/2013:14:07:11 -0800] [Job 472] End of messages
D [28/Feb/2013:14:07:11 -0800] [Job 472] printer-state=3(idle)
D [28/Feb/2013:14:07:11 -0800] [Job 472] printer-state-message="/usr/lib/cups/backend/lpd failed"
D [28/Feb/2013:14:07:11 -0800] [Job 472] printer-state-reasons=none
我现在不知道该怎么办。我尝试过以下方法：
- 删除打印机并重新安装
- 关闭并打开打印机
- 停止并重新启动杯子
有什么想法吗？这是否需要在系统管理员级别进行修复？