How to Fix Missing Icons in FreeCAD

Missing or invisible icons in the FreeCAD user interface typically stem from corrupted configuration files, incompatible custom themes, High-DPI display scaling glitches, or missing Qt SVG dependencies. This guide covers direct, practical troubleshooting methods to identify the source of the issue and restore your toolbar and menu icons to normal working order.

1. Reset the User Theme and Style Sheet

Custom or outdated UI themes often lack definitions for newer SVG icons or render them invisible against similar background colors.

  1. Open FreeCAD and navigate to Edit > Preferences.
  2. Under the General section, select the General tab.
  3. Locate the Style sheet dropdown menu and change it back to Default.
  4. Click Apply, then OK, and restart FreeCAD to see if the icons reload correctly.

2. Clear or Reset the Configuration Files

Corrupted cache files or broken settings in your user configuration can prevent Qt from loading the icon registry. Resetting these files creates a clean slate without requiring a full reinstallation.

  1. Close FreeCAD completely.
  2. Navigate to your operating system's configuration directory:
    • Windows: %APPDATA%\FreeCAD\ (e.g., C:\Users\<Username>\AppData\Roaming\FreeCAD\)
    • Linux: ~/.config/FreeCAD/ and ~/.local/share/FreeCAD/
    • macOS: ~/Library/Application Support/FreeCAD/ and ~/Library/Preferences/FreeCAD/
  3. Locate the user.cfg and system.cfg files.
  4. Rename user.cfg to user.cfg.bak.
  5. Launch FreeCAD. The application will generate a clean configuration file automatically.

3. Adjust High-DPI Display Scaling

When operating on 4K or multi-monitor setups with fractional scaling (such as 125% or 150%), the Qt framework may fail to render icon pixmaps properly.

  • Windows:
    1. Right-click the FreeCAD shortcut and select Properties.
    2. Switch to the Compatibility tab and click Change high DPI settings.
    3. Check Override high DPI scaling behavior and set the dropdown to Application or System (Enhanced).
    4. Save the settings and restart FreeCAD.
  • Linux:

    • If launching via the terminal, test running FreeCAD with disabled automatic scaling by executing:

      QT_AUTO_SCREEN_SCALE_FACTOR=0 freecad

    • Alternatively, force scale factors using:

      QT_SCALE_FACTOR=1 freecad

4. Install Missing Qt SVG Libraries (Linux Only)

On Linux distributions, package managers occasionally install FreeCAD without bundling the necessary SVG rendering modules for Qt.

  1. Open your system terminal.
  2. Install the Qt SVG library for your distribution:
    • Ubuntu/Debian: sudo apt install libqt5svg5 (or libqt6svg6 if using Qt6 builds)
    • Fedora: sudo dnf install qt5-qtsvg (or qt6-qtsvg)
    • Arch Linux: sudo pacman -S qt5-svg (or qt6-svg)
  3. Restart FreeCAD to allow the interface to render vector-based icons.

5. Reinstall Broken Addon Workbenches

If the missing icons are restricted to a single external workbench (such as Fasteners, BIM, or SheetMetal), the workbench assets may have failed to download completely.

  1. Open FreeCAD and go to Tools > Addon Manager.
  2. Locate the affected workbench in the Workbenches tab.
  3. Click Uninstall, then restart FreeCAD.
  4. Open the Addon Manager again, reinstall the workbench, and restart once more.

6. Perform a Clean Reinstallation

If the issue persists across all workbenches and the default theme fails to load assets, core program files may be corrupt. Uninstall FreeCAD, manually delete the leftover installation and AppData directories, and install the latest stable build from the official FreeCAD releases.