[Ubuntu Wiki] Update of "DebuggingPrintingProblems" by till-kamppeter

[Ubuntu Wiki]

Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Ubuntu Wiki" for change notification.

The "DebuggingPrintingProblems" page has been changed by till-kamppeter:
http://wiki.ubuntu.com/DebuggingPrintingProblems?action=diff&rev1=76&rev2=77

   8. Check via the command <<BR>> {{{$ file ~/printout}}} <<BR>> what format the file is. It is usually PDF or PostScript. Display the file on the screen to see whether the problem already occurs (error message, missing characters, wrong colors, ...). If you see the problem already, the application is the culprit, assign your bug report to the application's package, otherwise assign it to the "cups" package.
   9. Attach the original file of your application and the ~/printout file to your bug report.
  
+ = USB printer does not print or prints garbage =
+ 
+ There are some USB printers who do not work when the standard communication through the USB is applied. For these exception rules need to get implemented in the USB backend of CUPS.
+ 
+ If your printer is connected via USB try the following steps to find out whether such exception rules could solve your problem:
+ 
+  1. Does your printer also allow to be connected via network? Or does your router have a USB port which can be used to make a network printer out of a USB printer? Try out these connection methods. If your printer works with them, continue with the following steps. Continue also with the following steps if you do not have possibilities to use your printer as a network printer. Otherwise, your printer has a problem which does not fall into this class.
+ 
+  2. Make sure your printer is connected via USB again. Run the following command in a terminal window <<BR>> {{{$ cancel -a}}} <<BR>> {{{$ lpadmin -p <queue> -o usb-unidir-default=true}}} <<BR>> with <queue> being the print queue name of the printer with problems. Now your computer does purely uni-directional USB communication with your printer. Does printing work correctly now? Run <<BR>> {{{$ lpadmin -p <queue> -R usb-unidir-default}}} <<BR>> to remove this change.
+ 
+  3. Run <<BR>> {{{$ cancel -a}}} <<BR>> {{{$ lpadmin -p <queue> -o usb-no-reattach-default=true}}} <<BR> to make the USB backend not re-attach the usblp kernel module after the communication with the printer. Does printing work correctly for you now? Undo this change via <<BR>> {{{$ lpadmin -p <queue> -R usb-no-reattach-default}}}.
+ 
+ Please report a bug on the package "cups", preferably by running the command <<BR>> {{{$ ubuntu-bug cups]]] <<BR>>, reporting your results of the tests above and pasting in the output of the <<BR>> {{{$ lsusb}}} <<BR> command.
+ 
  = Problems installing the CUPS package =
  
  Most problems of installing the CUPS package are due to the CUPS daemon not starting after the installation or update of the package and this often happens when something is not OK with the configuration settings in '''/etc/cups/cupsd.conf'''.