This article discusses multiple steps to troubleshoot OS Activation errors in Mac OS X.
OS Activation errors are the result of the Operating System preventing a font from being activated. Below are the most common steps used to address OS Activation errors.
Note: On Mac OS X 10.8 and later, you may run into activation errors when you try to activate many fonts at once. This is due to a bug with the fontworker process built into Mac OS X which handles the internals of font activation. To work around this problem, wait for a couple of minutes and then try activating fewer fonts at a time.
Removing unnecessary fonts from the Local and User system font folders can clear up many font related problems and conflicts. For instructions on cleaning the system font folders, follow the directions listed in the "Manually cleaning up your System Font and Application Font folders" section of our Fonts Best Practices Guide: Best Practices for Managing Fonts in Mac OS X. Once the Local and User system font folders are cleaned out, restart the computer.
Note: UTS administrators can do this remotely for multiple clients simultaneously by enabling the System Font Policy in the UTS Users and Groups management
atsutil databases -removeUser
sudo atsutil databases -remove
~/Library/Application Support/Font Book/and trash the fb.db file.
~/Library/Fontsand have Font Book validate the fonts.