Ensure all characters (letters, numbers, symbols) are present.
For most users, web-based converters are the fastest solution: CloudConvert : Highly reliable for converting directly to ConvertFiles : Specifically supports conversions, which is common for older Mac system fonts. CloudConvert Professional "Repacking" Tools dmg font to ttf repack
import os, subprocess from fontTools.ttLib import TTFont Ensure all characters (letters
: Apple often packages fonts as Data Fork TrueType ( .dfont ) or Font Suitcases . These contain multiple font variants in a single container that standard Windows or Linux font installers cannot read directly. symbols) are present. For most users
7-Zip (Windows) or The Unarchiver (macOS)
This method is time-consuming but 100% free and transparent.