Check to see if the following fonts are installed: FretBoa, FretBoard, Screen Fonts, Mosaic Screen Fonts, MosaiFon, Vivo, and Vivo.suit (version 1.45 and later). If these are not installed, you will need to do a custom install of Mosaic's fonts from the Mosaic installer program. If they are installed, move on the next solution.

If you have too many fonts in your System’s Fonts folder, Mosaic will not be able to access the fonts it needs. As a test, remove any unnecessary fonts from the Fonts folder (found in your System folder) to a new folder on your desktop. To keep things organized call this folder “Temporary Fonts.” Be sure to keep FretBoa, FretBoard Screen Fonts, Mosaic Screen Fonts, MosaiFon, Vivo, and Vivo.suit as Mosaic needs these. After this, restart your computer and reopen Mosaic. If all is well, then too many fonts were in the Fonts folder. If Mosaic still shows stange fonts, try this next solution.

It’s possible that there is a Font ID conflict in your System. To fix this, move all fonts from your System’s Fonts folder to “Temporary Fonts” folder, the one we created earlier on your desktop. You will probably need to leave Chicago, Charcoal, and perhaps Geneva in the Fonts folder, and your Mac will warn you if you need to keep others in there. Close the Fonts folder, and open your main hard drive folder so that you can see your System folder. When you drag a font on top of the System folder, you will be asked if you want to store this font in the System’s Fonts folder. Drag all the fonts from the “Temporary Fonts” folder on to the System folder and choose OK when prompted. This will reorganize the fonts and their IDs. After this, restart your Mac and open Mosaic again. Mosaic should now display fonts normally.