Hushmail has been in the secure email service business since 1999. It offers end-to-end encryption through OpenPGP and scans all emails for viruses. Sending encrypted emails is straightforward since it's automatic between Hushmail accounts, and requires only a button push to send secure messages to contacts from other email services. There is sadly no free plan, but you can try the software through its 14-day free trial. On top of that, if after the two weeks you decide to buy the service, it's possible to test it even further through its 60-day money-back guarantee.
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