FontAgent Pro 6 is not supported on macOS Sierra. The version of FontAgent that we are supported on macOS Sierra is FontAgent 7, which is a paid upgrade from previous versions of FontAgent Pro.
If you were happy with the performance of FontAgent Pro 6, you can reinstall the older version, but please know that FontAgent Pro 6 is not supported on Sierra.
You can download the latest version of FontAgent Pro that does not include the alert at the link below:
Click to download: FontAgent Pro 6.502
Once you have reinstalled the 6.502 you will not want to inadvertently update to the 6.504 version. I suggest turning off your "Automatically Check for FontAgent Pro updates" option from Apple menu > FontAgent Pro > Preferences (uncheck box).
Known issues that v6 users who have moved to Sierra may see:
- Interface display problems
- Unexpected delay and hangs when opening the font database
- Inability to activate PostScript fonts installed in non-standard locations
- Issues with System Font Management
- Extended computer boot time
We would like to encourage to update to a supported version, but we also understand if you don’t wish to upgrade at this time.
We apologize for any inconvenience and would like to thank you for using FontAgent Pro.