Encrypting and decrypting emails by S/MIME

How to encrypt and decrypt emails to ensure to the email recipients that you actually sent the email and to have the possibility to check if received email is authentic. Which tools can be used to achieve secure S/MIME email?
1 answer

Encrypting and decrypting emails by S/MIME

1. Configure mail application for example Thunderbird. S/MIME does not work in the browser.
2. Generate your public and private key using for example ssl or extension to your mail application.
3. Create a certificate signing request using for example ssl.
4. Send request to "third Party" authority. There are many free and payed authorities, however the second ones are more trustworthy.
5. Download signed certificate and certificate of the authority.
6. Import signed certificate and certificate of the authority to mail client.
7. Now you can sign your emails by the certificate.