A few Windows installations have a legacy, and redundant, Windows Group Policy setting called 'Untrusted Font Blocking' enabled, and this prevents all applications from loading private fonts. We believe that this, redundant Group Policy, may only be set for Windows 10 installations upgraded from Windows versions earlier than Windows 10, but whatever the reason, it should be disabled.
How can I fix it?
For all editions of Windows 10, including Windows Home editions
Download 'disable_untrusted_fonts.reg' from here: https://updates.macrium.com/reflect/utilities/disable_untrusted_fonts.reg
Double click the downloaded file and click 'Yes' in the prompt:
Note: You must fully restart your PC after changing this setting.
You can perform a full shut down by pressing and holding the Shift key on your keyboard while you click the “Shut Down” option in Windows. This works whether you’re clicking the option in the Start menu, on the sign-in screen, or on the screen that appears after you press Ctrl+Alt+Delete.
For Windows 10 Pro and higher operating systems
Windows 10 Pro and higher installations have the option to edit the policy in the Windows Control Panel, without running the registry file.