Project Export looping / Optical Flow rendering looping

Have a project that I have export problems with. I have earlier been able to export the project with no issue. After the final editing and feel it is done Im unable to export it.

1. First always it complained that not all Optical Flow was rendered when exporting (Happens from time to time but FCPX never says what clip that has the missing Optical Flow render. Have also looked in ideos with this export error but not found any clip that is missing Optical Flow rendering). Ignored it. The project got stuck at about 4-5% and just stood there. CPU working. Can stand there for hours with no progress.
2. So tested to export "for Facebook" because that worked at one other project. That didnt work.
3. Tested to copy/paste all the edits to a new project within that library. Didnt work.
4. Removed all rendered material in Final Cut Pro. Didnt work.
5. Went in to the project file and removed all optical flow rendered material. FCP said it needed to render Optical flow material, allowed it and then later exported. Optical flow wasnt rendered.
6. Found Render All option. It loops at one clip (dont know which). Goes to 13 or maybe 16% and then loops.

I am out if ideas. Have searched but not found anything to solve this issue.

Macos 10.14
FCPX 10.4.10

That optical flow message is a bug, ignore it, you should be fine.

Thanks for the answer. Problem is that I cant export the project correctly. First it stops at about 4-5% and loop some rendering. Then I tried to remove all preview and optical flow rendered file in the project to re-render them . That loops at one unknown clip at about 13-16%. I can export it without the optical flow but the video clips that I have slows down dont have the 30 fps and is choppy. Can use that export but dont look good.

Is there a way to know what clip that loops the rendering of video / optical flow rendering or a way for FORCE it to render and not loop for ever?

What do you mean by "loops the rendering"? I don't understand? How is it looping?

When Final Cut Pro renders the Optical Flow at a clip it only goes to a few percent and then does it again, again, again, again, again. Never to 100%. It just stands there doing same thing over and over for hours with no progress in the rendering of the Optical Flow material. Endless loop....

In the project before i tested to delete the Optical Flow material that also stands in a loop of few percent and then redo it, again, again, again for hours. Tested to render it when going to sleep and it still do the same thing in the morning.

Project it stuck. Only solution I can see is to redo the project from scratch and that I do not want to do because it has so many small edits that will take long time to find and redo.

Thanks

How many clips are you using Optical Flow in, and how long is this Project timeline? I've never seen this behavior before.

Did solve the problem with a workaround. Was able to find the clip that looped with Optical Flow rendering and did create a new project, copied the settings and did render it there. Imported it as a normal clip and could render the final clip.

Curious that this clip havnt had any problem before with the rendering in other videos. Maybe for some reason have become corrupt and FCPX have problem reading it.

Thanks for our help.

Could be corruption of that specific Project's data, not the clip.