Do you need a free computer Certificate for S/MIME encryption?

Try this.  Using Open Source tools can be complicated for the average person.

“StartSSL™ is the trade mark of the StartCom Certification Authority – a leader of the digital certification industry. We provide you with everything from free low-assurance SSL certificates up to the most advanced PKI and security solutions for your business and personal use.”

via StartSSL™ Certificates.