Add Custom Font Fallback Link Using Regedit

This article explains how to configure custom font fallbacks in Windows by modifying the Windows Registry using the Registry Editor (Regedit). Font linking allows Windows to automatically substitute characters from a secondary font whenever a glyph or character is missing from the primary font. Following the step-by-step instructions below, you will learn how to access the proper registry directory, create the necessary multi-string entries, and properly format the font fallback references.

Prerequisites

Before making changes, ensure you have: * Administrator privileges on the Windows machine. * The file name and the internal family name of the fallback font you wish to link. Both must be installed in the C:\Windows\Fonts directory.

Step-by-Step Guide to Adding a Font Fallback

1. Open the Registry Editor

  1. Press Win + R on your keyboard to open the Run dialog box.
  2. Type regedit and press Enter.
  3. Click Yes if prompted by User Account Control (UAC).

In the Registry Editor address bar, paste the following path and press Enter:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\FontLink\SystemLink

3. Create or Select the Base Font Entry

  1. In the left-hand navigation pane, select the SystemLink key.
  2. In the right-hand pane, look for the base font to which you want to add a fallback (for example, Segoe UI, Arial, or Consolas).
  3. If the base font entry does not exist:
    • Right-click an empty space in the right pane.
    • Select New > Multi-String Value.
    • Name the value after the exact base font name (e.g., Consolas).

4. Add the Fallback Font Value

  1. Double-click the Multi-String Value corresponding to your base font.

  2. In the Value data field, enter the fallback font reference on a new line using this format:

    FILENAME.TTF,Font Family Name

    Example: To link the “Segoe UI Symbol” font, add: SEGUISYM.TTF,Segoe UI Symbol

  3. If you want to link multiple fallback fonts, list each font on its own separate line. Windows processes the fallback list from top to bottom.

  4. Click OK to save the values.

5. Restart Windows

Font link changes do not apply immediately. To apply the new font fallback configuration: * Restart your computer, or sign out and sign back in to your Windows account.