Delete Generated Library Files in Final Cut Pro

Follow these instructions to delete all previously rendered files from your Library. This can help diagnose or fix certain problems you may run into.

1) Launch Final Cut Pro

2) Select the Library

3) Select "Delete Generated Library Files…" under the "File" menu:

4) When the confirmation dialog appears, enable the "Delete Render Files" option and click OK:

We may sometimes instruct you to remove Optimized Media or Proxy Media as well. This is dependent on the type of problem you are trying to solve. Optimized Media refers to versions of your clips that have been re-encoded into ProRes for better performance during editing operations. Proxy Media refers to smaller, more efficient copies of your clips. Please refer to this document for more information:

https://support.apple.com/guide/final-cut-pro/create-optimized-and-proxy-files-verb8e5f6fd