Backups of your settings, and restoring one

What Castellan backs up#

Castellan backs up settings, not files: its own settings, and each agent's settings and the small things you'd miss if they were lost, such as what you've approved, dismissed or acknowledged, and what the Warrener's Put back needs to undo a move.

It never backs up your documents, photos or code, nor anything that can be made again: an agent's program, its models, its search index, caches, logs or downloads. A backup is small: a file over 5 MB is left out, and so is anything past 50 MB in all.

When#

• Once a day, while Castellan runs. A day the PC was off is caught up a couple of minutes after it starts.
• Before every update it installs, so an update can be undone.
• When you ask: Back up now, under Settings > Backups.

Nothing is stopped for a backup: the agents keep working. A file an agent has open at that moment is tried again a few times, then left out of that backup.

Where#

Until you choose a folder, backups go to %LOCALAPPDATA%\Castellan\Backups, on this PC only. OneDrive never copies that folder, so your backups don't leave the PC unless you choose a folder that does.

To keep them somewhere else, such as another drive (so they outlive this PC's drive), set Back up to under Settings > The manor. The folder must be outside every agent's own folder; Castellan refuses one that isn't, and says why. Settings > Backups shows the full path in use.

How many are kept#

Backups kept (under Settings > The manor) is 14 until you change it, from 1 to 365. Besides those, the newest 14 made just before an update are kept too, so an update can be undone weeks later. Older ones are removed after each new backup.

Each backup is one zip, named for the manor and the time: Manor-Castellan-2026-10-09-0930.zip.

Restore a backup#

1. Open Settings, and open Backups, at the end.
2. Choose Restore… on the backup you want.
3. Castellan shows what restoring it would change, file by file: added, changed, or as it is now. Choose everything in it, or one agent's settings.
4. Choose Restore.

Each agent with files to write is stopped, its files are written and checked, and it's started again. Whether an agent is on duty stays as it is now. An agent that won't stop is left as it was, with nothing of it written, and the restore says so. A restore can't run while an update does.

When backups fail#

If backups fail two days running, or the folder they go to can't be reached (a drive or network share that isn't there), it shows in Needs you across the top of Castellan's page, and Settings > Backups opens by itself to show what's wrong. Usually the fix is to plug the drive back in, or choose another folder under Back up to.