Comment 3 for bug 518263

I experienced the same problem on upgrade from 32-bit 8.04 to 10.04.

'sudo dpkg --configure -a' returns nothing
'sudo apt-get -f install flashplugin-nonfree' returns :

You might want to run `apt-get -f install' to correct these:
The following packages have unmet dependencies:
  flashplugin-nonfree: Depends: flashplugin-installer but it is not going to be installed
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

'sudo apt-get -f install flashplugin-installer' returns:
dpkg: error processing flashplugin-nonfree (--remove):
 Package is in a very bad inconsistent state - you should
 reinstall it before attempting a removal.
Errors were encountered while processing:
 flashplugin-nonfree
E: Sub-process /usr/bin/dpkg returned an error code (1)