Page 4 – Next: Multiple Email Addresses, Exchanging Certificates, Sending Encrypted Email
A “Gotcha” for Those With Multiple Email Addresses in the Same Account
If you’re using certificates for multiple email addresses within the same account, things get a bit hairy. You’ll need to choose each certificate at least once in the Settings > Mail > [Account] > Advanced > S/MIME sections for both Sign and Encrypt by Default. After each one, be sure to save changes by tapping Advanced > Account > Done, as above.
If you’re using certificates for multiple email addresses within the same account (multiple From: addresses), things get a bit hairy. You’ll need to choose each certificate at least once in the Settings > Mail > [Account] > Advanced > S/MIME sections for both Sign and Encrypt by Default. After each one, be sure to save changes by tapping Advanced > Account > Done, as above.
It seems that selecting the certificates here activates them for Mail to use for future signing and encrypting. Additionally, based on our tests, it doesn’t seem to matter which certificate is checked here, just so long as each of them has been checked at least once.
Exchange Certificates With Your Recipients
In order for encrypting email with iOS Mail to work, you have to exchange public certificates with your recipients. Simply send an email, asking for a reply back after your recipient has followed the same steps. Forward this article to your recipients so they can follow all of the required steps.
When you receive the reply from your recipient, there should be a blue check mark beside their email address, along with a tick. Now you need to install their public certificate on your iPhone or iPad. Tap the check mark or the email address to get to the next step in doing so.
The next screen tells you the recipient signed the email with a trusted certificate. Tap on View Certificate to begin installing the public certificate into the iOS Keychain.
You’ll see the certificate on the next screen, with an option near the bottom to Install. Tap that menu item, then tap Done in the top right corner.
Make sure your recipient does this too. Your recipient won’t be able to open your encrypted email if they don’t.
Send Your First Encrypted Email
Now you should be able to send encrypted email with iOS Mail. Go into the Mail app, and compose a new message. After you’ve typed in your recipient’s email address or chosen it from the address book, tap in the To: field again. You should see a blue lock to the right, just beneath the Send button. Tap the unlocked blue lock. That tells Mail to send an encrypted email. Leave the lock alone if it is already locked.
Now, go ahead and type out your email, and tap Send. Mail will send your encrypted email. Nobody will be able to read it without your public key.