Symptom

You completed a Mac Migration Assistant process to a new machine and K9 now says "K9 Not Responding"

Solution

The Mac Migration Assistant doesn't copy K9 Web Protection correctly to the new machine.  To fix K9, download the latest Mac version from the downloads page, and install K9 again on the new machine.  You will need to reboot after the installation.  Unfortunately, this will not retain the previous settings.  You will need to rest any configuration that was not part of the default configuration.

If this does not solve the issue, please contact support here.