compressor error

first time having an issue with this in compressor.
i recently started using LUT gallery so this is the first time trying to export through compressor using this.
this is also a 4k exporting as 1080. normally i just use the 1080 to 1080.
it seems to render fine in FCP. I tried to do a small clip of the total video and it completed the render.

Are you deleting all render files first (via File menu)?
Are you using Send To Compressor?

im am using send to compressor. i'm not deleting all render files. Do i need to? I've not done that before and don't know exactly how to.

Select your Library.
File menu, you'll see an option that says something like "Delete All Generated Library File".
That results in a window that will give you an option to delete ALL render files.
It's a good first step towards troubleshooting.

so still having some issues with exporting files via compressor. i generally like to have compressor send 1080 video to youtube which has worked fine thus far. i recently just exported via compressor to desktop and it worked.
Just did some edits on video and tried to do the same and get this error.

I am not completely sure, but I think I had the same issue once: I was trying to export a in different ratio, than the project in Final Cut Pro X was. (I think the project was something like 4:3, and it did not work with Compressor)
If it does not work, then try contacting the support.

Wait, just another thought: You might have to wait until FCP X has rendered in the background and of course don't close Final Cut Pro X while Compressor is working.