How can I fix this? The operation couldn’t be completed. (com.apple.Compressor.CompressorKit.ErrorDomain error -1.)

The Compressor Kit Error message has been reported with increasing frequency

of late. No universal fix so far, although lately users with the problem have

been able to fix it by updating/upgrading iMovie and, if necessary, the

operating system.  Also sometimes successful is starting up in Safe Mode (see Finder

menu for instructions) and then after everything loads immediately shutting down

and rebooting in normal mode.

Here's a link, though older, that describes what others have tried with the

Compressor Kit Error:

https://discussions.apple.com/thread/8265338

There may be some proposed solutions in the above link that will work for

you.

All else failing, try calling Apple Support. The techs there are very savvy

and also have the capability of remotely accessing your computer. Click on the

Contact Support item in the upper right hand corner of this screen and navigate

to a place where you can provide your telephone number so that Apple Support

can call you back. I think that the file path is Contact Support/Mac OS/Applications/iMovie,

or something like that.

Good luck with this. If you have time, post back with your results, as it

may assist others who have this perplexing issue.

-- Rich

That's great! Thanks for posting back. So many people have been struggling with the CompressorKit error and have tried numerous solutions without success. Although no global fix yet, it appears that updating or redownloading has been the most consistent fix.

-- Rich