Comment 3 for bug 975367

There are many dupes of bug 870643, where flashplugin-installer fails because it was unable to get the file it needs, over the internet.

This one may be different, because the DpkgTerminalLog.txt says:

Setting up flashplugin-installer (11.2.202.228ubuntu2) ...
update-alternatives: error: no alternatives for mozilla-flashplugin.
dpkg: error processing flashplugin-installer (--configure):
 subprocess installed post-installation script returned error exit status 2

So I'm not duping this one, though perhaps someone will judge it a dupe. I don't know what's happening with the alternatives.

To users newly seeing this problem, if you see errors that 'archive.canonical.com' was not reachable, or the download failed in other ways, I think 870643 is affecting you. Thanks.