Deactivating Font Book: Apple Support Communities. Thanks Kurt! I never deleted Font Book before and other programs like Font Explorer X seemed to work just fine. So it isn’t a requirement for all programs.

FEX won’t work right until you get Font Book off the drive. You don’t need to deactivate your fonts with it first.

As you know, the OS states “Font Book can’t be modified or deleted because it’s required by Mac OS X” when you try to delete it. Which is baloney. It’s just a font manager.

Actually, it says the same thing about any app you try to delete from the Applications folder. So, Chess is required by OS X? Umm, I don’t think so.

To get rid of Font Book in Lion:

1) First open the preferences for Font Book and turn off the check box for “Alert me if system fonts change”. Close the preferences and then shut down Font Book.

2) Open the Terminal application in the Utilities folder. Copy the following line.

sudo rm -R /Applications/Font\ Book.app

Paste it into Terminal. Press Enter. You will be asked for your admin password. Type it in (Terminal does not return on screen what you’re typing for a password) and press Enter. Politely wave bye-bye to Font Book.

3) Restart into a Safe Mode boot and then back again normally to clear Font Book’s orphaned database from the drive.