Install it on macOS:
- Download cert bundle (
.p7b) or individual certs (zipped) from DigiCert - Double click to install them on macOS Keychain Access
Install it on iOS:
- Open Keychain Access, select category My Certificates
- Right click and choose Export, select format
.p12(Make sure to export your cert into.p12, this will contain private key for iOS to send encrypted emails) - Email it with your individual certs (root CAs from DigiCert) and install them on iOS
- Select this cert under email account settings