How do I remove a s/mime certificate for a contact in iOS7 mail.app?
I'm using s/mime for two-way encrypted emails with several colleagues. A new colleague tried to install s/mime in Outlook for Windows and he sent me a signed email which I opened in iOS and trusted the certificate.
Then he changed his mind and stopped using s/mime (trouble with Outlook). iOS still tries to encrypt the email messages I send to him so he sees blank messages. I can find no way to list the certificates I have trusted for my contacts so I can remove this certificate.
Where do I have to look?