Folder not found
A request used a folder id that does not resolve (member folder nav, folder comments, move/upload targets, and similar).
Why this happens
Stale bookmark, wrong id, or deleted folder. Public /folder/[id] pages more often use a generic Next 404 / “Folder” fallback title — not always this exact API string.
Diagnose and fix
1. Open My Files and copy a current folder id.
2. Refresh UIs that cached old folder paths.
3. Recreate the folder if it was deleted.
4. For public folder sharing, confirm Public folders is enabled and the link is still valid.