Unreal Engine won't render video

I made a short movie in Unreal 5.1. I clicked the rendering button in Sequencer. I push the Capture movie but I only get this message on the bottom of the window.
unreal
Can you tell me what the problem is? I’m a super-rookie.

This means that either the Videos directory you’re trying to write to, is owned by some other user than the user currently running the editor, OR it doesn’t exist so it’s not writable.

Which OS are you using?