Every apt-get install returns flashplugin error, but install works

Question

I have recently installed Ubuntu 11.10 using wubi. I am now still in the process of installing my development environments. I have seen the following error occur multiple times.

For example, just now I wanted to install vim using the commmand sudo apt-get install vim. The following error is returned:

Fehler traten auf beim Bearbeiten von:  
("Errors were encountered while processing:" [via Google Translate])
  flashplugin-downloader:i386
  flashplugin-installer
  E: Sub-process /usr/bin/dpkg returned an error code (1)

The install seems to have completed and I can now use vim. Still, I would like to know what this error is and how I can fix it.

Answer 1

This error simply means flashplugin-installer didn't install correctly before, and you will need to reinstall it.

Run:

sudo apt-get remove --purge flashplugin-installer
sudo apt-get update
sudo apt-get install flashplugin-installer

Answer 2

This flashplugin problem often happen when you are behind proxy. Right now, flashplugin-installer does not work if you are behind a proxy, bcause it tries to download it directly, not via the proxy. Even if you applied the settings systemwide.

My workaround is, the following:

Two things need to be done:

• Edit your /etc/environment file and add the following line to it: HTTP_PROXY="http://your_proxy_addess:proxy_port"
• Edit your sudoers file by sudo visudo (use the EDITOR environment variable to specify the editor if you don't like vi), and add the following line before the Defaults env_reset one: Defaults env_keep="http_proxy"

Now it should install fine, via sudo apt-get install --reinstall flashplugin-installer

If the update notifier bugs you on every startup, you may want to delete this file:

/var/lib/update-notifier/package-data-downloads/flashplugin-installer.failed

Answer 3

I'm also behind proxy. Thank you Calmarius.

As root, I typed these lines in the terminal to get flashplugin installed:

• export http_proxy=http://192.168.0.1:8080
• apt-get install --reinstall flashplugin-installer