I have been using and recommending Thawte’s free SMIME email certificates for a number of years. Personal email certificates have always been a bit more attractive for me than PGP for communicating securely with other [not always very computer literate] people since they are directly integrated into most [if not all] email clients.

It’s always been nice to be able to sign an email to another person with my certificate, and just tell them to hit the “encrypt” button next time they send me something either of us want encrypted :-) (email clients automatically store a certificate after receiving it, which signing includes).

Thawte has been my choice for SMIME certificates because they issue them for free, and it’s not something that’s really worth paying for. There are other services out there that do the same kind of thing for free, but Thawte is a large name I trust. Unfortunately, Thawte recently announced that they are closing down their free email certificate program.

I have been using PGP for a few years to communicate with multiple people too, and have decided to try and move all my friends/clients over to it too due to the circumstances. Also, PGP has the major advantage of you creating your own private keys instead of a 3rd party (i.e. Thawte) doing it, meaning only you have the key to access emails encrypted to you.

So anywho, here’s the info on getting PGP set up with Thunderbird in Windows for anyone that needs it.

• First, of course, you’ll need Thunderbird, which can be downloaded here.
• I recommend you always send all your emails in both HTML and Plain Text, so you can have rich text formatting in your emails by default, but lame people that don’t have clients that read HTML are ok too. To do this, go to Menu > Tools > Options > Composition > General > Send Options > In the top box change it to “Send the message in both plain text and HTML”.
• Next, you need to install PGP. I recommend using GnuPG (windows version).
• When you run GnuPG for the first time, it’ll ask you if you want to generate a key, which you’ll want to do, unless you already have one made that you need to import.
• Next, you’ll want to install Enigmail for Thunderbird. After downloaded it, in Thunderbird, go to Menu > Tools > Add-ons > Extensions > Install, and open the .xpi file.
• After Thunderbird restarts, go to Menu > OpenPGP > Setup Wizard and step through it. During this setup, I personally suggest changing the following default options:
  • “Do you want to change a few default settings...” > Yes > Details > Uncheck the following
    • Disable flowed text
    • View message body as plain text
    • Use 8-bit encoding for message sending
    • Do not compose HTML message
• To encrypt mail to other people, or verify a signed message from them, you need their public key file. Some of the ways they can send their public key to you are as follows:
  • A normal file send, in which case you will need to import it through GnuPG.
  • You might also be able to retrieve it from a public key server if they put it there, but I am not going to go into that.
  • If they send it to you through an attachment in an email, and you double click on it in Thunderbird, you will receive a prompt asking if you’d like to import the key.
• To encrypt an email to another person, after having their public key, simple go to Menu > OpenPGP > Encrypt Message in the compose window. Make sure to also check Menu > OpenPGP > Use PGP/MIME for This Message so it can send the HTML!
• To send your public key to someone go to Menu > OpenPGP > Attach My Public Key in the compose window.