Sometimes your Mac wants to connect to a server which cannot be verified. If this is a server you don’t recognize or haven’t used before, you should probably cancel and contact the owner of the server.
If it’s your own company server or if you’re connecting to a shared contacts address book or email system, you can override these security settings to avoid repeatedly seeing the notification.
Verifying a certificate
- Click Show Certificate.
- Check Always trust.
- Click Continue.
- Type your computer’s login password. This is the one you use to get to your desktop – it may not match the password on the server. Then Update Settings.
Learn more about security & troubleshooting.