Unable to Export Video

In line with what Ben said, make sure you have at least 20% free disk space on your system drive and on your export drive.

In line with what Terry said, do this:

• Duplicate your project timeline
• Open the duplicate
• Select all clips via CMD+A
• Delete all effects from all clips via Edit > Remove Effects
• Try to export the timeline without effects
• If that works, do CMD+Z to restore all effects
• Select 1/2 of the timeline clips and do Edit > Remove Effects
• Try export
• Continue as above, on 1/4 of timeline, 1/8, etc. until you narrow down the problematic effect

Try pre-rendering the regular timeline containing all effects:

• Select all clips via CMD+A
• Render all clips to cache via CTRL+R
• Observe the render dots above the timeline. Make sure they all go away, meaning it's fully rendered.
• If an error happens during that render operation, report the details.
• If it renders to cache OK, try to export it.
• Tip: If you have the space and can export to ProRes 422, that will happen super fast on a pre-rendered timeline.

FCP has an export optimization called "Export Segmentation," whereby multiple encoders will export pieces of the timeline in parallel, then transparently assemble them to a single file. I think it is limited to Max and Ultra machines. However, as a troubleshooting step, please check that "Export Segmentation" is disabled. See attached.

Error -17691, kVTSessionMalfunctionErr, is a low-level error from the macOS VideoToolbox framework. All it tells us is something went wrong (which we already know).

There is probably more data in your macOS log, maybe a crash file. If you run the macOS Console app it gives easy access to those. To launch console just do CMD+spacebar and type "console."

Then, in the left sidebar, click on crash reports. If there is any FCP crash shown, right-click on that to reveal the .ips file. Send me that file here: https://we.tl/r-bAQQU51kIi

Immediately after one of these problems, I would also like to see a two-minute excerpt of your macOS system log. You can produce that with this command in terminal. To run terminal just do CMD+spacebar and type "terminal."

sudo log show --info --debug --style syslog --last 2m > ~/Documents/LogShow2m.txt

It will prompt for your password, so enter that. The file will be in your /Documents folder. Send me that file also to the above URL. Make sure you issue the command immediately after the problem (ie within about 30 seconds).

As Ben said, it might be related to a corrupt media file. As he said, in FCP click on the library in the left sidebar. Then do File > Delete Generated Library Files > Delete Render Files > All.

If you have not rebooted your machine in a while, go ahead and do that.

If it still has problems, shut down FCP and launch it while holding the OPT and CMD keys. That will delete FCP preferences, which often helps with mysterious problems. You will have to re-enter a few preferences in FCP > Settings, but that is quick and easy.

Try setting an Out point mid-project, and export roughly the first half. Does that go through?

Do the same for the second half.

If they both succeed, then you have gotten yourself a workaround. Just collate the two together, using FCP or even Quicktime Player.

If one of the two fails, then proceed the divide and conquer process. You may find that there is a problem clip or effect somewhere, and you can edit around that.

SoaringOverTexas wrote:

Still working at it to no success... one thing I noticed is the every one of these exports makes a mp4 segment (unusable) appear in the destination place - if that's any bit of useful info

What are your export settings? "Computer"?

You could try selecting "Export File", "Video and Audio", and choose ProRes (but beware that this produces a huge file), or H264. This produces a mov file.

If half the timeline is still a lot, try a smaller section. Does that work?

Can you export the last minute? What about the last 5 minutes? Since you successfully exported the first 50% you've got to divide and conquer to figure out where in the last 50% the issue is. I had an issue a few months ago where on an M4 Pro Mac Mini, a very large image was causing the export to silently fail. Opening the library on an M1 Ultra Mac Studio and the project exported fine. It took several range exports starting at a few different places to determine where the issue was.

If you have multiple media files with the same filename, FCP must add a "uniquifier" suffix to tell them apart.

E.g, if you have three files in different disk folders, all named "File.m4a," FCP upon import will internally name those "File(fcp1).m4a", "File(fcp2).m4a," "File(fcp3).m4a," etc.

That is an internal-only name. Normally, you don't even see that unless you look inside the library package with Finder. Do NOT rename those in Finder.

If you have a red "missing media" clip in your timeline, do this:

• Click on the red missing media clip in your timeline
• Do SHIFT+F to find it in the Event Browser
• Select the red missing media clip in the Event Browser
• Do File > Relink Files > Original Media
• Stop and do NOT relink it. Rather look at the grey pathname in the relink dialog (see attached)
• That pathname is where FCP thinks the file should be. Does that tell you anything about why the file isn't there? Does it ring any bells?

Do not rename them.

It looks like your drive may have some issues.

In addition to all the good advice already given, you may want to run Disk Utility and check the drives. Does the "First Aid" report any problems?

As Luis Sequeira1 has already mentioned, you could theoretically try a different codec. My sense of troubleshooting tells me it doesn’t really make sense if the first half worked, but it’s more than certainly worth a try.

I won’t suggest things like drive formatting and all that either as that’ll be useless.

While I wonder, how be it that the regular export would get to a theoretical amount of 70% if the entire latter 50% of the project seem to fail exporting now (it shouldn’t be that much)?

This will likely not help with your issue directly, yet allow me to ask if it fails to export when using compressor too?

Verify you have minimum 15% free space on your system drive.

Delete all render files, first.

The "(fcp1)" is added to a file that has the same name as a file you already imported, that's all.

And no, NEVER rename a file in the Finder once it's imported. Those file names are NOT your issues.

If FCP claims files are missing, were these specific files originally from a camera card? Or from some other source?

Good luck! Feel free to return to this thread, I'll see if I can find anything in the meantime.