Font issues are one of the more common reasons a computer might act up. They can cause the computer to slow down, apps to crash, and many other annoyances. Fortunately, OS X has some simple tools to help manage fonts and avoid these issues.
In the Applications folder on a Mac is a program called Font Book. This is Apple’s font management program. Whenever new fonts are installed on a Mac, they are added to Font Book by default. When Font Book is opened, it displays a list of all the fonts on the computer. It also has the ability to sort those fonts into groups, previewing functionality, and several other features.
Two common font issues that can affect a computer’s performance are duplicate fonts and corrupted fonts. Font Book can easily identify and help you fix either of these issues.
To quickly check for and fix duplicate fonts, choose EDIT, LOOK FOR ENABLED DUPLICATES. Font Book will search your fonts, and, if duplicates are found, give you the choice to RESOLVE MANUALLY or RESOLVE AUTOMATICALLY. If you choose to have Font Book resolve the duplicates automatically, Font Book will disable one copy of each of the duplicates it finds.
Disabling does not actually delete the duplicate font, but essentially turns it off so it does affect the system. It can be re-enabled by the user at any time.
If you choose to resolve the duplicate manually, Font Book will show you each of the duplicates in a window that allows you to view both copies and disable the one of your choice.
To have Font Book search your fonts for any corrupted files, first select all the fonts you want searched (to select all, click one font then press Command-A). A separate FONT VALIDATION window will open and label the selected fonts as PASSED (a green circle and checkmark), WARNING (a yellow circle and exclamation point), or ERROR (a red circle and x).
Fonts with a yellow warning have small problems, like a duplicate font or kerning table issues. These should be used cautiously, but probably won’t cause any serious issues. Fonts with a red error have more serious problems, and should probably be removed from your system. To remove fonts directly from the FONT VALIDATION window, just check the box to the left of the font(s) you want removed, then click REMOVE CHECKED.
Jason Merrill, Mac & iOS Consultant