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<h1>Email Self-Defense</h1>

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<p>We fight for computer users' rights, and promote the development of free (as
in freedom) software. Resisting bulk surveillance is very important to us.</p>

<p><strong>Please donate to support Email Self-Defense. We need to keep
improving it, and making more materials, for the benefit of people around
the world taking the first step towards protecting their privacy.</strong></p>

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<!-- ~~~~~~~~~ Guide Introduction ~~~~~~~~~ -->
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<p><a id="infographic" href="infographic.html"><img
src="//static.fsf.org/nosvn/enc-dev0/img/en/infographic-button.png"
alt="View &amp; share our infographic &rarr;" /></a>
Bulk surveillance violates our fundamental rights and makes free speech
risky. This guide will teach you a basic surveillance self-defense skill: email
encryption. Once you've finished, you'll be able to send and receive emails
that are scrambled to make sure a surveillance agent or thief intercepting
your email can't read them. All you need is a computer with an Internet
connection, an email account, and about forty minutes.</p>

<p>Even if you have nothing to hide, using encryption helps protect the privacy
of people you communicate with, and makes life difficult for bulk surveillance
systems. If you do have something important to hide, you're in good company;
these are the same tools that whistleblowers use to protect their identities
while shining light on human rights abuses, corruption and other crimes.</p>

<p>In addition to using encryption, standing up
to surveillance requires fighting politically for a <a
href="http://gnu.org/philosophy/surveillance-vs-democracy.html">reduction
in the amount of data collected on us</a>, but the essential first step is
to protect yourself and make surveillance of your communication as difficult
as possible. This guide helps you do that. It is designed for beginners, but
if you already know the basics of GnuPG or are an experienced free software
user, you'll enjoy the advanced tips and the <a href="workshops.html">guide
to teaching your friends</a>.</p>

</div><!-- End .intro -->
</div></header><!-- End #header -->

<!-- ~~~~~~~~~ Section 1: Get the pieces ~~~~~~~~~ -->
<section class="row" id="section1"><div>

<!-- ~~~~~~~~~ section introduction: interspersed text ~~~~~~~~~ -->
<div class="section-intro">

<h2><em>#1</em> Get the pieces</h2>

<p class="notes">This guide relies on software which is <a
href="https://www.gnu.org/philosophy/free-sw.html">freely licensed</a>;
it's completely transparent and anyone can copy it or make their
own version. This makes it safer from surveillance than proprietary
software (like Windows). Learn more about free software at <a
href="https://u.fsf.org/ys">fsf.org</a>.</p>

<p>Most GNU/Linux operating systems come with GnuPG installed on them,
so you don't have to download it. Before configuring GnuPG though, you'll
need the IceDove desktop email program installed on your computer. Most
GNU/Linux distributions have IceDove installed already, though it may be
under the alternate name "Thunderbird." Email programs are another way to
access the same email accounts you can access in a browser (like Gmail),
but provide extra features.</p>

<p>If you already have an email program, you can skip to <a
href="#step-1b">Step 1.b</a>.</p>

</div><!-- End .section-intro -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-1a" class="step">
<div class="sidebar">

<p><img
src="//static.fsf.org/nosvn/enc-dev0/img/en/screenshots/step1a-install-wizard.png"
alt="Step 1.A: Install Wizard" /></p>

</div><!-- /.sidebar -->
<div class="main">

<h3><em>Step 1.a</em> Set up your email program with your email account</h3>

<p>Open your email program and follow the wizard (step-by-step walkthrough)
that sets it up with your email account.</p>

<p>Look for the letters SSL, TLS, or STARTTLS to the right of the servers
when you're setting up your account. If you don't see them, you will still
be able to use encryption, but this means that the people running your email
system are running behind the industry standard in protecting your security
and privacy. We recommend that you send them a friendly email asking them
to enable SSL, TLS, or STARTTLS for your email server. They will know what
you're talking about, so it's worth making the request even if you aren't
an expert on these security systems.</p>

<!-- ~~~~~~~~~ Troubleshooting ~~~~~~~~~ -->
<div class="troubleshooting">

<h4>Troubleshooting</h4>

<dl>
<dt>The wizard doesn't launch</dt>
<dd>You can launch the wizard yourself, but the menu option for doing so is
named differently in each email program. The button to launch it will be in
the program's main menu, under "New" or something similar, titled something
like "Add account" or "New/Existing email account."</dd>

<dt>The wizard can't find my account or isn't downloading my mail</dt>
<dd>Before searching the Web, we recommend you start by asking other people
who use your email system, to figure out the correct settings.</dd>

<dt class="feedback">Don't see a solution to your problem?</dt>
<dd class="feedback">Please let us know on the <a
href="https://libreplanet.org/wiki/GPG_guide/Public_Review">feedback
page</a>.</dd>
</dl>

</div><!-- /.troubleshooting -->
</div><!-- End .main -->
</div><!-- End #step1-a .step -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-1b" class="step">
<div class="sidebar">
<ul class="images">
<li><img src="//static.fsf.org/nosvn/enc-dev0/img/en/screenshots/step1b-01-tools-addons.png"
alt="Step 1.B: Tools -> Add-ons" /></li>
<li><img src="//static.fsf.org/nosvn/enc-dev0/img/en/screenshots/step1b-02-search.png"
alt="Step 1.B: Search Add-ons" /></li>
<li><img src="//static.fsf.org/nosvn/enc-dev0/img/en/screenshots/step1b-03-install.png"
alt="Step 1.B: Install Add-ons" /></li>
</ul>

</div><!-- /.sidebar -->
<div class="main">

<h3><em>Step 1.b</em> Install the Enigmail plugin for your email program</h3>

<p>In your email program's menu, select Add-ons (it may be in the Tools
section). Make sure Extensions is selected on the left. Do you see Enigmail?
Make sure it's the latest version. If so, skip this step.</p>

<p>If not, search "Enigmail" with the search bar in the upper right. You
can take it from here. Restart your email program when you're done.</p>

<p>There are major security flaws in versions of GnuPG prior to 2.2.8, and
Enigmail prior to 2.0.7. Make sure you have GnuPG 2.2.8 and Enigmail 2.0.7,
or later versions.</p>

<!-- ~~~~~~~~~ Troubleshooting ~~~~~~~~~ -->
<div class="troubleshooting">

<h4>Troubleshooting</h4>

<dl>
<dt>I can't find the menu.</dt>
<dd>In many new email programs, the main menu is represented by an image of
three stacked horizontal bars.</dd>

<dt>My email looks weird</dt>
<dd>Enigmail doesn't tend to play nice with HTML, which is used to format
emails, so it may disable your HTML formatting automatically. To send an
HTML-formatted email without encryption or a signature, hold down the Shift
key when you select compose. You can then write an email as if Enigmail
wasn't there.</dd>

<dt class="feedback">Don't see a solution to your problem?</dt>
<dd class="feedback">Please let us know on the <a
href="https://libreplanet.org/wiki/GPG_guide/Public_Review">feedback
page</a>.</dd>
</dl>

</div><!-- /.troubleshooting -->
</div><!-- End .main -->
</div><!-- End #step-1b .step -->
</div></section><!-- End #section1 -->

<!-- ~~~~~~~~~ Section 2: Make your keys ~~~~~~~~~ -->
<section class="row" id="section2"><div>

<!-- ~~~~~~~~~ section introduction: interspersed text ~~~~~~~~~ -->
<div class="section-intro">

<h2><em>#2</em> Make your keys</h2>

<p>To use the GnuPG system, you'll need a public key and a private key (known
together as a keypair). Each is a long string of randomly generated numbers
and letters that are unique to you. Your public and private keys are linked
together by a special mathematical function.</p>

<p>Your public key isn't like a physical key, because it's stored in the open
in an online directory called a keyserver. People download it and use it,
along with GnuPG, to encrypt emails they send to you. You can think of the
keyserver as a phonebook; people who want to send you encrypted email can
look up your public key.</p>

<p>Your private key is more like a physical key, because you keep it to
yourself (on your computer). You use GnuPG and your private key together to
descramble encrypted emails other people send to you. <span style="font-weight:
bold;">You should never share you private key with anyone, under any
circumstances.</span></p>

<p>In addition to encryption and decryption, you can also use these keys to
sign messages and check the authenticity of other people's signatures. We'll
discuss this more in the next section.</p>

</div><!-- End .section-intro -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-2a" class="step">
<div class="sidebar">

<p><img
src="//static.fsf.org/nosvn/enc-dev0/img/en/screenshots/step2a-01-make-keypair.png"
alt="Step 2.A: Make a Keypair" /></p>

</div><!-- /.sidebar -->
<div class="main">

<h3><em>Step 2.a</em> Make a keypair</h3>

<p>The Enigmail Setup wizard may start automatically. If it doesn't, select
Enigmail &rarr; Setup Wizard from your email program's menu. You don't need
to read the text in the window that pops up unless you'd like to, but it's
good to read the text on the later screens of the wizard. Click Next with
the default options selected, except in these instances, which are listed
in the order they appear:</p>

<ul>
<li>On the screen titled "Encryption," select "Encrypt all of my messages
by default, because privacy is critical to me."</li>

<li>On the screen titled "Signing," select "Don't sign my messages by
default."</li>

<li>On the screen titled "Key Selection," select "I want to create a new
key pair for signing and encrypting my email."</li>

<li>On the screen titled "Create Key," pick a strong password! You can
do it manually, or you can use the Diceware method. Doing it manually
is faster but not as secure. Using Diceware takes longer and requires
dice, but creates a password that is much harder for attackers to figure
out. To use it, read the section "Make a secure passphrase with Diceware" in <a
href="https://theintercept.com/2015/03/26/passphrases-can-memorize-attackers-cant-guess/">
this article</a> by Micah Lee.</li>
</ul>

<p>If you'd like to pick a password manually, come up with something
you can remember which is at least twelve characters long, and includes
at least one lower case and upper case letter and at least one number or
punctuation symbol. Never pick a password you've used elsewhere. Don't use
any recognizable patterns, such as birthdays, telephone numbers, pets' names,
song lyrics, quotes from books, and so on.</p>

<p class="notes">The program will take a little while to finish the next
step, the "Key Creation" screen. While you wait, do something else with your
computer, like watching a movie or browsing the Web. The more you use the
computer at this point, the faster the key creation will go.</p>

<p><span style="font-weight: bold;">When the "Key Generation Completed" screen
pops up, select Generate Certificate and choose to save it in a safe place on
your computer (we recommend making a folder called "Revocation Certificate"
in your home folder and keeping it there). This step is essential for your
email self-defense, as you'll learn more about in <a href="#section5">Section
5</a>.</span></p>

<!-- ~~~~~~~~~ Troubleshooting ~~~~~~~~~ -->
<div class="troubleshooting">

<h4>Troubleshooting</h4>

<dl>
<dt>I can't find the Enigmail menu.</dt>
<dd>In many new email programs, the main menu is represented by an image
of three stacked horizontal bars. Enigmail may be inside a section called
Tools.</dd>

<dt>The wizard says that it cannot find GnuPG.</dt>
<dd>Open whatever program you usually use for installing software, and search
for GnuPG, then install it. Then restart the Enigmail setup wizard by going
to Enigmail &rarr; Setup Wizard.</dd>

<dt>More resources</dt>
<dd>If you're having trouble with our
instructions or just want to learn more, check out <a
href="https://www.enigmail.net/documentation/Key_Management#Generating_your_own_key_pair">
Enigmail's wiki instructions for key generation</a>.</dd>

<dt class="feedback">Don't see a solution to your problem?</dt>
<dd class="feedback">Please let us know on the <a
href="https://libreplanet.org/wiki/GPG_guide/Public_Review">feedback
page</a>.</dd>
</dl>

</div><!-- /.troubleshooting -->

<!-- ~~~~~~~~~ Troubleshooting ~~~~~~~~~ -->
<div class="troubleshooting">

<h4>Advanced</h4>

<dl>
<dt>Command line key generation</dt>
<dd>If you prefer using the command line for a higher
degree of control, you can follow the documentation from <a
href="https://www.gnupg.org/gph/en/manual/c14.html#AEN25">The GNU Privacy
Handbook</a>. Make sure you stick with "RSA and RSA" (the default),
because it's newer and more secure than the algorithms the documentation
recommends. Also make sure your key is at least 2048 bits, or 4096 if you
want to be extra secure.</dd>

<dt>Advanced key pairs</dt>
<dd>When GnuPG creates a new keypair, it compartmentalizes
the encryption function from the signing function through <a
href="https://wiki.debian.org/Subkeys">subkeys</a>. If you use
subkeys carefully, you can keep your GnuPG identity much more
secure and recover from a compromised key much more quickly. <a
href="https://alexcabal.com/creating-the-perfect-gpg-keypair/">Alex Cabal</a>
and <a href="http://keyring.debian.org/creating-key.html">the Debian wiki</a>
provide good guides for setting up a secure subkey configuration.</dd>
</dl>

</div><!-- /.troubleshooting -->
</div><!-- End .main -->
</div><!-- End #step-2a .step -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-2b" class="step">
<div class="main">

<h3><em>Step 2.b</em> Upload your public key to a keyserver</h3>

<p>In your email program's menu, select Enigmail &rarr; Key Management.</p>

<p>Right click on your key and select Upload Public Keys to Keyserver. Use
the default keyserver in the popup.</p>

<p class="notes">Now someone who wants to send you an encrypted message can
download your public key from the Internet. There are multiple keyservers
that you can select from the menu when you upload, but they are all copies
of each other, so it doesn't matter which one you use. However, it sometimes
takes a few hours for them to match each other when a new key is uploaded.</p>

<!-- ~~~~~~~~~ Troubleshooting ~~~~~~~~~ -->
<div class="troubleshooting">

<h4>Troubleshooting</h4>

<dl>
<dt>The progress bar never finishes</dt>
<dd>Close the upload popup, make sure you are connected to the Internet,
and try again. If that doesn't work, try again, selecting a different
keyserver.</dd>

<dt>My key doesn't appear in the list</dt>
<dd>Try checking "Display All Keys by Default."</dd>

<dt>More documentation</dt>
<dd>If you're having trouble with our
instructions or just want to learn more, check out <a
href="https://www.enigmail.net/documentation/Key_Management#Distributing_your_public_key">
Enigmail's documentation</a>.</dd>

<dt class="feedback">Don't see a solution to your problem?</dt>
<dd class="feedback">Please let us know on the <a
href="https://libreplanet.org/wiki/GPG_guide/Public_Review">feedback
page</a>.</dd>
</dl>

</div><!-- /.troubleshooting -->

<!-- ~~~~~~~~~ Troubleshooting ~~~~~~~~~ -->
<div class="troubleshooting">

<h4>Advanced</h4>

<dl>
<dt>Uploading a key from the command line</dt>
<dd>You can also upload your keys to a keyserver through the <a
href="https://www.gnupg.org/gph/en/manual/x457.html">command line</a>. <a
href="https://sks-keyservers.net/overview-of-pools.php">The sks Web site</a>
maintains a list of highly interconnected keyservers. You can also <a
href="https://www.gnupg.org/gph/en/manual/x56.html#AEN64">directly export
your key</a> as a file on your computer.</dd>
</dl>

</div><!-- /.troubleshooting -->
</div><!-- End .main -->
</div><!-- End #step-2b .step -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="terminology" class="step">
<div class="main">

<h3>GnuPG, OpenPGP, what?</h3>

<p>In general, the terms GnuPG, GPG, GNU Privacy Guard, OpenPGP and PGP
are used interchangeably. Technically, OpenPGP (Pretty Good Privacy) is the
encryption standard, and GNU Privacy Guard (often shortened to GPG or GnuPG)
is the program that implements the standard. Enigmail is a plug-in program
for your email program that provides an interface for GnuPG.</p>

</div><!-- End .main -->
</div><!-- End #terminology.step-->
</div></section><!-- End #section2 -->

<!-- ~~~~~~~~~ Section 3: Try it out ~~~~~~~~~ -->
<section class="row" id="section3"><div>

<!-- ~~~~~~~~~ section introduction: interspersed text ~~~~~~~~~ -->
<div class="section-intro">

<h2><em>#3</em> Try it out!</h2>

<p>Now you'll try a test correspondence with a computer program named Edward,
who knows how to use encryption. Except where noted, these are the same
steps you'd follow when corresponding with a real, live person.</p>

<!-- <p>NOTE: Edward is currently having some technical difficulties, so he
may take a long time to respond, or not respond at all. We're sorry about
this and we're working hard to fix it. Your key will still work even without
testing with Edward.</p> -->
</div><!-- End .section-intro -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-3a" class="step">
<div class="sidebar">

<p><img
src="//static.fsf.org/nosvn/enc-dev0/img/en/screenshots/section3-try-it-out.png"
alt="Try it out." /></p>

</div><!-- /.sidebar -->
<div class="main">

<h3><em>Step 3.a</em> Send Edward your public key</h3>

<p>This is a special step that you won't have to do when corresponding
with real people. In your email program's menu, go to Enigmail &rarr; Key
Management. You should see your key in the list that pops up. Right click
on your key and select Send Public Keys by Email. This will create a new
draft message, as if you had just hit the Write button.</p>

<p>Address the message to <a
href="mailto:edward-en@fsf.org">edward-en@fsf.org</a>. Put at least one word
(whatever you want) in the subject and body of the email. Don't send yet.</p>

<p>The lock icon in the top left should be yellow, meaning encryption is
turned on. We want this first special message to be unencrypted, so
click the icon once to turn it off. The lock should become grey, with a
blue dot on it (to alert you that the setting has been changed from the
default). Once encryption is off, hit Send.</p>

<p class="notes">It may take two or three minutes for Edward to
respond. In the meantime, you might want to skip ahead and check out the <a
href="#section5">Use it Well</a> section of this guide. Once he's responded,
head to the next step. From here on, you'll be doing just the same thing as
when corresponding with a real person.</p>

<p>When you open Edward's reply, GnuPG may prompt you for your password
before using your private key to decrypt it.</p>

</div><!-- End .main -->
</div><!-- End #step-3a .step -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-3b" class="step">
<div class="main">

<h3><em>Step 3.b</em> Send a test encrypted email</h3>

<p>Write a new email in your email program, addressed to <a
href="mailto:edward-en@fsf.org">edward-en@fsf.org</a>. Make the subject
"Encryption test" or something similar and write something in the body.</p>

<p>The lock icon in the top left of the window should be yellow, meaning
encryption is on. This will be your default from now on.</p>

<p class="notes">Next to the lock, you'll notice an icon of a pencil. We'll
get to this in a moment.</p>

<p>Click Send. Enigmail will pop up a window that says "Recipients not valid,
not trusted or not found."</p>

<p>To encrypt an email to Edward, you need his public key, so now you'll have
Enigmail download it from a keyserver. Click Download Missing Keys and use
the default in the pop-up that asks you to choose a keyserver. Once it finds
keys, check the first one (Key ID starting with C), then select ok. Select
ok in the next pop-up.</p>

<p>Now you are back at the "Recipients not valid, not trusted or not found"
screen. Check the box in front of Edward's key and click Send.</p>

<p class="notes">Since you encrypted this email with Edward's public key,
Edward's private key is required to decrypt it. Edward is the only one with
his private key, so no one except him can decrypt it.</p>

<!-- ~~~~~~~~~ Troubleshooting ~~~~~~~~~ -->
<div class="troubleshooting">

<h4>Troubleshooting</h4>

<dl>
<dt>Enigmail can't find Edward's key</dt>
<dd>Close the pop-ups that have appeared since you clicked Send. Make sure
you are connected to the Internet and try again. If that doesn't work, repeat
the process, choosing a different keyserver when it asks you to pick one.</dd>

<dt>Unscrambled messages in the Sent folder</dt>
<dd>Even though you can't decrypt messages encrypted to someone else's key,
your email program will automatically save a copy encrypted to your public key,
which you'll be able to view from the Sent folder like a normal email. This
is normal, and it doesn't mean that your email was not sent encrypted.</dd>

<dt>More resources</dt>
<dd>If you're still having trouble with our
instructions or just want to learn more, check out <a
href="https://www.enigmail.net/documentation/Signature_and_Encryption#Encrypting_a_message">
Enigmail's wiki</a>.</dd>

<dt class="feedback">Don't see a solution to your problem?</dt>
<dd class="feedback">Please let us know on the <a
href="https://libreplanet.org/wiki/GPG_guide/Public_Review">feedback
page</a>.</dd>
</dl>

</div><!-- /.troubleshooting -->

<!-- ~~~~~~~~~ Troubleshooting ~~~~~~~~~ -->
<div class="troubleshooting">

<h4>Advanced</h4>

<dl>
<dt>Encrypt messages from the command line</dt>
<dd>You can also encrypt and decrypt messages and files from the <a
href="https://www.gnupg.org/gph/en/manual/x110.html">command line</a>,
if that's your preference. The option --armor makes the encrypted output
appear in the regular character set.</dd>
</dl>

</div><!-- /.troubleshooting -->
</div><!-- End .main -->
</div><!-- End #step-3b .step -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-headers_unencrypted" class="step">
<div class="main">

<h3><em>Important:</em> Security tips</h3>

<p>Even if you encrypt your email, the subject line is not encrypted, so
don't put private information there. The sending and receiving addresses
aren't encrypted either, so a surveillance system can still figure out who
you're communicating with. Also, surveillance agents will know that you're
using GnuPG, even if they can't figure out what you're saying. When you
send attachments, Enigmail will give you the choice to encrypt them or not,
independent of the actual email.</p>

<p>For greater security against potential attacks, you can turn off
HTML. Instead, you can render the message body as plain text. In order
to do this in Thunderbird, go to View &gt; Message Body As &gt; Plain
Text.</p>

</div><!-- End .main -->
</div><!-- End #step-headers_unencrypted .step-->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-3c" class="step">
<div class="main">

<h3><em>Step 3.c</em> Receive a response</h3>

<p>When Edward receives your email, he will use his private key to decrypt
it, then use your public key (which you sent him in <a href="#step-3a">Step
3.A</a>) to encrypt his reply to you.</p>

<p class="notes">It may take two or three minutes for Edward to
respond. In the meantime, you might want to skip ahead and check out the <a
href="#section5">Use it Well</a> section of this guide.</p>

<p>When you receive Edward's email and open it, Enigmail will automatically
detect that it is encrypted with your public key, and then it will use your
private key to decrypt it.</p>

<p>Notice the bar that Enigmail shows you above the message, with information
about the status of Edward's key.</p>

</div><!-- End .main -->
</div><!-- End #step-3c .step -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-3d" class="step">
<div class="main">

<h3><em>Step 3.d</em> Send a test signed email</h3>

<p>GnuPG includes a way for you to sign messages and files, verifying that
they came from you and that they weren't tampered with along the way. These
signatures are stronger than their pen-and-paper cousins -- they're impossible
to forge, because they're impossible to create without your private key
(another reason to keep your private key safe).</p>

<p>You can sign messages to anyone, so it's a great way to make people
aware that you use GnuPG and that they can communicate with you securely. If
they don't have GnuPG, they will be able to read your message and see your
signature. If they do have GnuPG, they'll also be able to verify that your
signature is authentic.</p>

<p>To sign an email to Edward, compose any message to him and click the
pencil icon next to the lock icon so that it turns gold. If you sign a
message, GnuPG may ask you for your password before it sends the message,
because it needs to unlock your private key for signing.</p>

<p>With the lock and pencil icons, you can choose whether each message will
be encrypted, signed, both, or neither.</p>

</div>
</div>

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-3e" class="step">
<div class="main">

<h3><em>Step 3.e</em> Receive a response</h3>

<p>When Edward receives your email, he will use your public key (which you
sent him in <a href="#step-3a">Step 3.A</a>) to verify that your signature
is authentic and the message you sent has not been tampered with.</p>

<p class="notes">It may take two or three minutes for Edward to
respond. In the meantime, you might want to skip ahead and check out the <a
href="#section5">Use it Well</a> section of this guide.</p>

<p>Edward's reply will arrive encrypted, because he prefers to use encryption
whenever possible. If everything goes according to plan, it should say
"Your signature was verified." If your test signed email was also encrypted,
he will mention that first.</p>

</div><!-- End .main -->
</div><!-- End #step-3e .step -->
</div></section>

<!-- ~~~~~~~~~ Section 4: Learn the Web of Trust ~~~~~~~~~ -->
<section class="row" id="section4"><div>

<!-- ~~~~~~~~~ section introduction: interspersed text ~~~~~~~~~ -->
<div class="section-intro">

<h2><em>#4</em> Learn the Web of Trust</h2>

<p>Email encryption is a powerful technology, but it has a weakness;
it requires a way to verify that a person's public key is actually
theirs. Otherwise, there would be no way to stop an attacker from making
an email address with your friend's name, creating keys to go with it and
impersonating your friend. That's why the free software programmers that
developed email encryption created keysigning and the Web of Trust.</p>

<p>When you sign someone's key, you are publicly saying that you've verified
that it belongs to them and not someone else.</p>

<p>Signing keys and signing messages use the same type of mathematical
operation, but they carry very different implications. It's a good practice
to generally sign your email, but if you casually sign people's keys, you
may accidently end up vouching for the identity of an imposter.</p>

<p>People who use your public key can see who has signed it. Once you've
used GnuPG for a long time, your key may have hundreds of signatures. You
can consider a key to be more trustworthy if it has many signatures from
people that you trust. The Web of Trust is a constellation of GnuPG users,
connected to each other by chains of trust expressed through signatures.</p>

</div><!-- End .section-intro -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-4a" class="step">
<div class="sidebar">

<p><img
src="//static.fsf.org/nosvn/enc-dev0/img/en/screenshots/section4-web-of-trust.png"
alt="Section 4: Web of Trust" /></p>

</div><!-- /.sidebar -->
<div class="main">

<h3><em>Step 4.a</em> Sign a key</h3>

<p>In your email program's menu, go to Enigmail &rarr; Key Management.</p>

<p>Right click on Edward's public key and select Sign Key from the context
menu.</p>

<p>In the window that pops up, select "I will not answer" and click ok.</p>

<p>Now you should be back at the Key Management menu. Select Keyserver &rarr;
Upload Public Keys and hit ok.</p>

<p class="notes">You've just effectively said "I trust that Edward's public
key actually belongs to Edward." This doesn't mean much because Edward isn't
a real person, but it's good practice.</p>

<!--<div id="pgp-pathfinder">

<form enctype="application/x-www-form-urlencoded" action="/mk_path.cgi"
method="get">

<p><strong>From:</strong><input type="text" value="xD41A008"
name="FROM"></p>

<p><strong>To:</strong><input type="text" value="50BD01x4" name="TO"></p>

<p class="buttons"><input type="submit" value="trust paths" name="PATHS"><input
type="reset" value="reset" name=".reset"></p>

</form>

</div>End #pgp-pathfinder -->
</div><!-- End .main -->
</div><!-- End #step-4a .step -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-identify_keys" class="step">
<div class="main">

<h3>Identifying keys: Fingerprints and IDs</h3>

<p>People's public keys are usually identified by their key fingerprint,
which is a string of digits like F357AA1A5B1FA42CFD9FE52A9FF2194CC09A61E8
(for Edward's key). You can see the fingerprint for your public key, and
other public keys saved on your computer, by going to Enigmail &rarr; Key
Management in your email program's menu, then right clicking on the key
and choosing Key Properties. It's good practice to share your fingerprint
wherever you share your email address, so that people can double-check that
they have the correct public key when they download yours from a keyserver.</p>

<p class="notes">You may also see public keys referred to by a shorter
key ID. This key ID is visible directly from the Key Management
window. These eight character key IDs were previously used for
identification, which used to be safe, but is no longer reliable. You
need to check the full fingerprint as part of verifying you have the
correct key for the person you are trying to contact. Spoofing, in
which someone intentionally generates a key with a fingerprint whose
final eight characters are the same as another, is unfortunately
common.</p>

</div><!-- End .main -->
</div><!-- End #step-identify_keys .step-->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="check-ids-before-signing" class="step">
<div class="main">

<h3><em>Important:</em> What to consider when signing keys</h3>

<p>Before signing a person's key, you need to be confident that it actually
belongs to them, and that they are who they say they are. Ideally, this
confidence comes from having interactions and conversations with them over
time, and witnessing interactions between them and others. Whenever signing
a key, ask to see the full public key fingerprint, and not just the shorter
key ID. If you feel it's important to sign the key of someone you've just
met, also ask them to show you their government identification, and make
sure the name on the ID matches the name on the public key. In Enigmail,
answer honestly in the window that pops up and asks "How carefully have you
verified that the key you are about to sign actually belongs to the person(s)
named above?"</p>

<!-- ~~~~~~~~~ Troubleshooting ~~~~~~~~~ -->
<div class="troubleshooting">

<h4>Advanced</h4>

<dl>
<dt>Master the Web of Trust</dt>
<dd>Unfortunately, trust does not spread between users the way <a
href="http://fennetic.net/irc/finney.org/~hal/web_of_trust.html">many people
think</a>. One of best ways to strengthen the GnuPG community is to deeply <a
href="https://www.gnupg.org/gph/en/manual/x334.html">understand</a> the Web of
Trust and to carefully sign as many people's keys as circumstances permit.</dd>

<dt>Set ownertrust</dt>
<dd>If you trust someone enough to validate other people's keys, you can assign
them an ownertrust level through Enigmails's key management window. Right
click on the other person's key, go to the "Select Owner Trust" menu option,
select the trustlevel and click OK. Only do this once you feel you have a
deep understanding of the Web of Trust.</dd>
</dl>

</div><!-- /.troubleshooting -->
</div><!-- End .main -->
</div><!-- End #check-ids-before-signing .step-->
</div></section><!-- End #section4 -->

<!-- ~~~~~~~~~ Section 5: Use it well ~~~~~~~~~ -->
<section id="section5" class="row"><div>

<!-- ~~~~~~~~~ section introduction: interspersed text ~~~~~~~~~ -->
<div class="section-intro">

<h2><em>#5</em> Use it well</h2>

<p>Everyone uses GnuPG a little differently, but it's important to follow
some basic practices to keep your email secure. Not following them, you
risk the privacy of the people you communicate with, as well as your own,
and damage the Web of Trust.</p>

</div><!-- End .section-intro -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-5a" class="step">
<div class="sidebar">

<p><img
src="//static.fsf.org/nosvn/enc-dev0/img/en/screenshots/section5-01-use-it-well.png"
alt="Section 5: Use it Well (1)" /></p>

</div><!-- /.sidebar -->
<div class="main">

<h3>When should I encrypt? When should I sign?</h3>

<p>The more you can encrypt your messages, the better. If you only encrypt
emails occasionally, each encrypted message could raise a red flag for
surveillance systems. If all or most of your email is encrypted, people
doing surveillance won't know where to start. That's not to say that only
encrypting some of your email isn't helpful -- it's a great start and it
makes bulk surveillance more difficult.</p>

<p>Unless you don't want to reveal your own identity (which requires other
protective measures), there's no reason not to sign every message, whether or
not you are encrypting. In addition to allowing those with GnuPG to verify
that the message came from you, signing is a non-intrusive way to remind
everyone that you use GnuPG and show support for secure communication. If you
often send signed messages to people that aren't familiar with GnuPG, it's
nice to also include a link to this guide in your standard email signature
(the text kind, not the cryptographic kind).</p>

</div><!-- End .main -->
</div><!-- End #step-5a .step -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-5b" class="step">
<div class="sidebar">

<p><img
src="//static.fsf.org/nosvn/enc-dev0/img/en/screenshots/section5-02-use-it-well.png"
alt="Section 5: Use it Well (2)" /></p>

</div><!-- /.sidebar -->
<div class="main">

<h3>Be wary of invalid keys</h3>

<p>GnuPG makes email safer, but it's still important to watch out for invalid
keys, which might have fallen into the wrong hands. Email encrypted with
invalid keys might be readable by surveillance programs.</p>

<p>In your email program, go back to the first encrypted email that Edward
sent you. Because Edward encrypted it with your public key, it will have a
message from Enigmail at the top, which most likely says "Enigmail: Part of
this message encrypted."</p>

<p><b>When using GnuPG, make a habit of glancing at that bar. The program
will warn you there if you get an email signed with a key that can't
be trusted.</b></p>

</div><!-- End .main -->
</div><!-- End #step-5b .step -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-5c" class="step">
<div class="main">

<h3>Copy your revocation certificate to somewhere safe</h3>

<p>Remember when you created your keys and saved the revocation certificate
that GnuPG made? It's time to copy that certificate onto the safest digital
storage that you have -- the ideal thing is a flash drive, disk, or hard
drive stored in a safe place in your home, not on a device you carry with
you regularly.</p>

<p>If your private key ever gets lost or stolen, you'll need this certificate
file to let people know that you are no longer using that keypair.</p>

</div><!-- End .main -->
</div><!-- End #step-5c .step -->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="step-lost_key" class="step">
<div class="main">

<h3><em>Important:</em> act swiftly if someone gets your private key</h3>

<p>If you lose your private key or someone else gets ahold
of it (say, by stealing or cracking your computer), it's
important to revoke it immediately before someone else uses
it to read your encrypted email or forge your signature. This
guide doesn't cover how to revoke a key, but you can follow these <a
href="https://www.hackdiary.com/2004/01/18/revoking-a-gpg-key/">instructions</a>.
After you're done revoking, make a new key and send an email to everyone
with whom you usually use your key to make sure they know, including a copy
of your new key.</p>

</div><!-- End .main -->
</div><!-- End #step-lost_key .step-->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<!---<div id="transfer-key" class="step">
<div class="main">

<h3>Transferring you key</h3>

<p>You can use Enigmail's <a
href="https://www.enigmail.net/documentation/Key_Management">key management
window</a> to import and export keys. If you want to be able to read
your encrypted email on a different computer, you will need to export
your secret key from here. Be warned, if you transfer the key without <a
href="https://help.ubuntu.com/community/EncryptedFilesystemsOnRemovableStorage">encrypting</a>
the drive it's on the transfer will be dramatically less secure.</p>

</div>--><!-- End .main
</div> End #transfer-key .step-->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~ -->
<div id="webmail-and-GnuPG" class="step">
<div class="main">

<h3>Webmail and GnuPG</h3>

<p>When you use a web browser to access your email, you're using webmail,
an email program stored on a distant website. Unlike webmail, your desktop
email program runs on your own computer. Although webmail can't decrypt
encrypted email, it will still display it in its encrypted form. If you
primarily use webmail, you'll know to open your email client when you receive
a scrambled email.</p>

</div><!-- End .main -->
</div><!-- End #webmail-and-GnuPG .step-->

<!-- ~~~~~~~~~ a div for each step ~~~~~~~~~
<div id="step-5d" class="step">
<div class="main">

<h3>Make your public key part of your online identity</h3>

<p> First add your public key fingerprint to your email signature, then
compose an email to at least five of your friends, telling them you just
set up GnuPG and mentioning your public key fingerprint. Link to this guide
and ask them to join you. Don't forget that there's also an awesome <a
href="infographic.html">infographic to share.</a></p>

<p class="notes">Start writing your public key fingerprint anywhere someone
would see your email address: your social media profiles, blog, Website,
or business card. (At the Free Software Foundation, we put ours on our
<a href="https://fsf.org/about/staff">staff page</a>.) We need to get our
culture to the point that we feel like something is missing when we see an
email address without a public key fingerprint.</p>

</div>--><!-- End .main
</div> End #step-5d .step-->
</div></section><!-- End #section5 -->

<!-- ~~~~~~~~~ Section 6: Next steps ~~~~~~~~~ -->
<section class="row" id="section6">
<div id="step-click_here" class="step">
<div class="main">

<h2><a href="next_steps.html">Great job! Check out the next steps.</a></h2>

</div><!-- End .main -->
</div><!-- End #step-click_here .step-->
</section><!-- End #section6 -->

<!-- ~~~~~~~~~ FAQ ~~~~~~~~~ -->
<!-- When un-commenting this section go to main.css and search
for /* Guide Sections Background */ then add #faq to the desired color
<section class="row" id="faq"><div>
<div class="sidebar">

<h2>FAQ</h2>

</div>
<div class="main">

<dl>
<dt>My key expired</dt>
<dd>Answer coming soon.</dd>

<dt>Who can read encrypted messages? Who can read signed ones?</dt>
<dd>Answer coming soon.</dd>

<dt>My email program is opening at times I don't want it to open/is now my
default program and I don't want it to be.</dt>
<dd>Answer coming soon.</dd>
</dl>

</div>
</div>
</section> --><!-- End #faq -->

<!-- ~~~~~~~~~ Footer ~~~~~~~~~ -->
<footer class="row" id="footer"><div>
<div id="copyright">

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src="//static.fsf.org/nosvn/enc-dev0/img/fsf-logo.png" /></a></h4>

<p>Copyright &copy; 2014-2016 <a
href="https://u.fsf.org/ys">Free Software Foundation</a>, Inc. <a
href="https://my.fsf.org/donate/privacypolicy.html">Privacy Policy</a>. Please
support our work by <a href="https://u.fsf.org/yr">joining us as an associate
member.</a></p>

<p>The images on this page are under a <a
href="https://creativecommons.org/licenses/by/4.0/">Creative Commons
Attribution 4.0 license (or later version)</a>, and the rest of it is under
a <a href="https://creativecommons.org/licenses/by-sa/4.0">Creative Commons
Attribution-ShareAlike 4.0 license (or later version)</a>. Download the <a
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available under the GNU Affero General Public License. <a
href="http://www.gnu.org/licenses/license-list.html#OtherLicenses">Why these
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<p>Fonts used in the guide &amp; infographic: <a
href="https://www.google.com/fonts/specimen/Dosis">Dosis</a> by Pablo
Impallari, <a href="http://www.google.com/fonts/specimen/Signika">Signika</a>
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<p>Download the <a href="emailselfdefense_source.zip">source package</a>
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<p>This site uses the Weblabels standard for labeling <a
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