My C4D file says "Incorrect File Structure" or "Unknown File Format" – Can I recover my project?

Sometimes files can become corrupted due to various reasons, including:

Common error messages:

"Incorrect File Structure": It is usually possible to recover some or all of the corrupted file.
"Unknown File Format!": This means the file is too corrupt for recovery.

+Windows

Open Command Prompt (search for cmd).
Navigate to your Cinema 4D program folder (for example, C:\Program Files\Maxon\Cinema 4D 20XX).
Drag Cinema 4D.exe into the Command Prompt window.
Press space, then append -loadcorruptscenes and press Enter.
It should look similar to:

+macOS

Open Applications > Utilities > Terminal.
Navigate to your Cinema 4D application folder (for example, /Applications/Maxon/Cinema 4D 20XX).
Right‑click Cinema 4D.app → Show Package Contents, then open Contents/macOS.
Drag the Cinema 4D binary into the Terminal window.
Press space, append -loadcorruptscenes, and press Return.
It should look similar to:

Once Cinema 4D launches with the recovery flag, try opening your scene. The loader will recover whatever is possible.

Note: Recovery is “what you see is what you get” — data beyond what opens cannot be restored.

You can also watch a video walkthrough here.

Try the process on a different machine if possible, as different machines can produce different results.
If you have no other machines to try this on, please raise a support ticket here, and our team can attempt to recover the scene for you.