Mac and iPhone “connection is not secure”

(Like many of my technology postings, this is really here for my own notes on problems I run into, the solutions I try and what works when. They are updated as I learn.)

  • Open the Keychain Access app.
  • Select "System Roots" keychain.
  • Search for the issuing certificate authority.
  • View the certificate details (double click, expand the "Trust" area of the view window).
  • In my case, the trust rule was: "When using this certificate, ".
  • I changed it to "Always Trust", closed Keychain Access (after entering my admin password) and the page loaded.
  • Not wanting to leave it in a less secure mode, I used Keychain Access again and switched it back to "Use System Defaults".
  • Problem solved, no relaxation of security parameters.