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PGP in Claws Mail (Ubuntu 19.10 / 20.04)

So that your Email-provider, the police or an intelligence agency can‘t read your Emails on the way through the Internet you have to encrypt it with PGP. PGP stands for “Pretty good privacy“ and is a tool for encrypting and decrypting data that got released first in 1991. The public-key procedure is used, in which there is a public key and a private key.

The public key encrypts a file, but can‘t decrypt it. You can share the public key with other persons or upload it to a keyserver.

The private key decrypts a file, but can‘t encrypt it. It is protected with a password. You should take care of this key, because you should be the only person that can encrypt data that is meant for you. If you lose it, you won‘t be able to decrypt data that was encrypted with your public key.

But PGP is also not perfect, since the sender, receiver and subject cannot be encrypted. [1],[2],[3],[4],[5]

Example with Alice and Bob:

and generate both a public and a private key.
sends her to . / finds her on the Internet.
uses , to encrypt his Email for Alice.
sends the Email.
uses her to decrypt the Email.

Creating a pair of keys

1. $ sudo apt install gnupg2
//Installs GNU Privacy Guard

2. $ gpg2 --full-generate-key

3. Type in "1"

4. Type in "4096"
//You will create a RSA 4096 bit key

5. Choose "0"
//The key doesn't expire

6. Confirm with "Y"

7. Choose a name (shouldn't be a real one)

8. Type in your Email adress

9. Add a comment, or go on with "enter"

10. Confirm all your data with "O"

11. Enter a secure passphrase

12. $ gpg2 --export --armor myemail@account.com > mypublickey.asc

You can find your public key in /Home/

13. $ gpg2 --list-key
// should show your public key in your key ring

Importing a key to your key ring

1. $ gpg2 --import /Path/Example.key (or .gpg / .asc)

check with "gpg2 --list-key", if the key is in your key ring

Installing Claws

1. $ sudo apt install claws-mail

Login in Claws

about you

Type in a name and your real Email adress

receiving mail

Server address: disroot.org
Username: everything before the @
Password: your Email password
Check "Use SSL/TLS"

sending mail

SMTP server adress: disroot.org
Check "Use authentication"
Check "Use SSL/TLS"

Installing PGP-plugins

Enter "sudo apt-get install claws-mail-plugins claws-mail-extra-plugins" in your terminal

-> Install the plugins

Activating the PGP-Plugins




Sending an encrypted Email

Privacy System

1. Options -> Privacy System -> check "PGP MIME"
2. Options -> check "Sign" + "Encrypt"
3. Write your Email -> hit "Send"


Confirm with "Yes"


Enter your password from step 11

--> Now you have successfully sent an encrypted Email <--


[1] https://invidio.us/watch?v=inxNRA4xK1Q

[2] https://invidio.us/watch?v=RNZBzZuXZKk

[3] https://de.wikipedia.org/wiki/Pretty_Good_Privacy

[4] https://invidio.us/watch?v=CHi2RclGvIM

[5] https://www.gbs.com/de/email-verschluesselung

[6] https://digdeeper.neocities.org/ghost/email.html#encryption

[7] https://wiki.ubuntuusers.de/GnuPG