We are going to see how we can send encrypted emails using thunderbird, Enigmail and OpenPGP standard.
1. Download & Install GnuPG. You will find it here or sudo apt-get install gnupg for ubuntu users.
2. Download & Install Thunderbird. You will find it here or sudo apt-get install thunderbird for ubuntu users.
3. Download & Install Enigmail addon. You will find it here.
4. Open OpenPGP->Preferences, under Files and Directories you should see something like this: GnuPG was found in /path/to/gnupg/
5.1 Now you should configure your email accounts to use Enigmail. To do this Select Tools->Account Settings… or Edit->Account Settings…
5.2 On the left sidebar, under your Email Account, select OpenPGP Security. Check the box “Enable OpenPGP support (Enigmail) for this identity.”.
5.3 Select the radio button next to “Use email address of this identity to identify OpenPGP key.”.
5.4 Click OK.
6. Create your key pair. Select OpenPGP->Key Management. When the window opens, select from the menu, Generate->New Key Pair. Select which email address you would like to associate the key pair with. Choose your passphrase and click “Generate Key.”
7. Generate a revocation certificate!
8. Locate your Key ID. Select OpenPGP in the menu bar->Key Management->Enter your email address in the search box. You’ll see your key ID. Memorize it or write it down.
9. You could share your key ID. Publish it on the public keyserver network. Select OpenPGP->Key Management->Enter your emaill address->Right Click on your key and then click “Upload public keys to Keyserver.” Select “pool.sks-keyservers.net” and click OK.
10. Write a new email. Select OpenPGP->Sign Message or Encrypt Message. Don’t forget to attach your public key by Selecting OpenPGP->Attach my Public Key from Thunderbird’s main menu.
11. Now you can send your email. You will be prompted to enter your passphrase.