Troubleshooting Guide

If thumbnails do not appear for FCStd files after installing FreeCADPreview, try the following steps.

1 Launch FreeCADPreview

Open FreeCADPreview once after installation. This lets macOS register its Finder thumbnail extension.

2 Enable the extensions

Open System Settings > General > Login Items & Extensions > Extensions > Quick Look, then make sure the FreeCADPreview thumbnail extension is enabled.

3 Reset the thumbnail cache

Open Terminal, then run:

Return to Finder and reopen the folder containing your FCStd files.

4 Check the saved preview

FreeCADPreview reads the thumbnail saved inside an FCStd project. If a file has no saved thumbnail, open it in FreeCAD, save it again, and retry the preview.