Email messages and attachments can be intercepted as they are sent over the Internet. Many email providers support secure connections for incoming and outgoing email. However, the email protocol has a flaw: it falls-back to unsecure connections if an error happens.
Zimbra supports S/MIME a standard for encryption and signing email. By using S/MIME encryption you can enhance email privacy, so that only intended recipients can read the contents of email and attachments. S/MIME signing works similar to registered mail, if you receive an S/MIME signed email you can know for sure it really came from the person displayed on the screen.
In the Zimbra S/MIME Whitepaper you can learn how S/MIME works, what benefits it brings and how to use it with Zimbra and:
- iOS mail client
- Zimbra Desktop
Thanks for the whitepaper! But 15-Dec-2021? Zimbra Desktop became EOL on October 1, 2019 doesn’t it? What kind of sorcery is this?
IMHO validating s/mime signed emails with Zimbra is a bigger issue now, because the default java trust store is missing root certificates.
There is a Modern UI Zimbra desktop that is available via the Partner Portal.