I have solved this problem for Canon MX860 networked printer. Clues came from a report of a similar problem with Arch linux and from the cups error_log file.
During upgrade to 12.04, a key library was deleted. In my case it was libpopt.so.0.0.0. From my working Mint 12 installation I copied both the 64-bit version (in /lib) and the 32-bit version (in /lib32) to these folders on a sick 12.04 machine as root. I then created symbolic links to these files. That is: sudo cp /path to 64-bit source copy/libpopt.so.0.0.0 /lib/libpopt.so.0.0.0 cd /lib sudo ln -s libpopt.so.0.0.0 libpopt.so.0 sudo cp /path to 32-bit source copy/libpopt.so.0.0.0 /lib32/libpopt.so.0.0.0 cd /lib32 sudo ln -s libpopt.so.0.0.0 libpopt.so.0 I restarted cups with: sudo restart cups Finally, I completely removed then reinstalled the printer driver packages. In my case the packages were: cnijfilter-common_3.10-1_amd64.deb cnijfilter-mx860series_3.10-1_amd64.deb -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/992982 Title: Network printing fails. Worked before upgrade to 12.04 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/cups/+bug/992982/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs