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This question already has an answer here:

I am having problems installing Wifi Fern

@ubuntu:~/Desktop$ sudo dpkg -i Fern-Wifi-Cracker_1.6_all.deb

Selecting previously unselected package fern-wifi-cracker.
(Reading database ... 187540 files and directories currently installed.)
Unpacking fern-wifi-cracker (from Fern-Wifi-Cracker_1.6_all.deb) ...
dpkg: dependency problems prevent configuration of fern-wifi-cracker:
 fern-wifi-cracker depends on aircrack-ng; however:
  Package aircrack-ng is not installed.
 fern-wifi-cracker depends on subversion; however:
  Package subversion is not installed.
dpkg: error processing fern-wifi-cracker (--install):
 dependency problems - leaving unconfigured
Processing triggers for bamfdaemon ...
Rebuilding /usr/share/applications/bamf.index...
Processing triggers for desktop-file-utils ...
Processing triggers for gnome-menus ...
Errors were encountered while processing:

Can you help please?

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marked as duplicate by gertvdijk, Alvar, Thomas W., Jorge Castro, Basharat Sialvi Jun 20 '13 at 17:58

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

Install the dependencies

Run in the terminal:

sudo apt-get install -f

This will fulfil the dependencies missing - dpkg isn't capable of doing this. It will also configure (finish) the installation of Fern-Wifi-Cracker_1.6_all.deb automatically.

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Run the following in Terminal

sudo apt-get update
sudo apt-get upgrade

to update the system. Then:

sudo apt-get install aircrack-ng


sudo apt-get install subversion

Then try again. This will install aircrack-ng and subversion first, then when you run

sudo dpkg -i Fern-Wifi-Cracker_1.6_all.deb

It should work.


I have changed the code to reflect the comments on this question. Thank you for pointing them out.

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Actually a full list of dependencies is found here: – don.joey Jun 20 '13 at 13:35
Why are you advising to install build dependencies. He's not going to compile subversion and aircrack-ng here in the question, but he's installing a prebuilt binary package with regular dependencies. – gertvdijk Jun 20 '13 at 13:36
The question states that the dependencies aircrack-ng and subversion are not installed. How else is he going to install them? – SimplySimon Jun 20 '13 at 13:40
@SimplySimon If you are advising to install dependencies manually, then just use install, not build-dep. And I think installation of dependencies automatically as in my answer is a lot more user friendly. – gertvdijk Jun 20 '13 at 13:46
OK, when I tried it I found that supervision had dependencies so I used build-dep but it works with install so I will change my answer to reflect this. Thank you for your help :) – SimplySimon Jun 20 '13 at 14:11

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