Apply fails
What you see: after Apply, the notification says "That did not start", "The changes could not be applied", or the Overview's Changes widget lists the job as failed. The box keeps running its old settings.
What a failed Apply means
Nothing changed. A rebuild either completes and is switched in, or fails and leaves the previous system running. Your files are never involved.
Causes, most likely first
- A box from before 7 October 2026. Every Apply on an installed box answered "That did not start" because the rebuild command was not on the daemon's path. Pull request #71 fixed it; the 03:00 update brings the fix (the nightly update uses a different path and was not affected). Until then, settings cannot be changed from the panes.
- A box that is already rebuilding. The notification says so. Wait for the running job to finish (the Changes widget shows it) and apply again.
- The disk is full. A rebuild needs room. See Out of room.
- A setting the box cannot take. A name with a character the checks did not catch, a port in use. Discard, change one thing at a time, apply again, and see which one fails.
- The upgrade source is unreachable. If the box's upgrade source points at GitHub and the internet is down, a rebuild that needs to fetch fails. Wait, or apply once the internet is back. The box's own description never needs the internet.
What to do when it keeps failing
- Wait for the next 03:00: the nightly rebuild runs the same job with the same settings file and, if it fails too, leaves the box as it is.
- Settings → Reset puts every setting back and rebuilds from the defaults, which is the one description known to work on every box. Your files stay.
- Get help with the Changes widget's text for the failed job.