Why is "Not Secure" showing?  The certificate for HTTPS (SSL) has been upgraded to a newer type of security.  Old systems like Macs with Operating system before 10.12.1 have issue using the newer type of security. 


Options:


1. Upgrade your Operating System to the latest version.   If your computer is out of support to receive the latest operating system version then use option 2.


1.5. Update your browser version if Firefox or Chrome.


2. Use the work around on your operating system.

Directions for fix on Apple Mac:

  1. Open ~/Applications/Utilities/Keychain Access.app
  2. From View menu select "Show Expired Certificates"
  3. On the Left Sidebar pick "System Roots"
  4. In search bar top-right type DST
  5. Double-click "DST Root CA X3"
  6. In pop-up, turn down "Trust" arrow and set "When using this certificate" to "Always Trust"
  7. Close the pop-up and put in an Administrator user/password info.
  8. Close all open Browsers & Keychain you should be good to go after that.