{"name":"sandbox.failIfUnavailable","slug":"sandbox-failifunavailable","family":"setting","title":"Settings keys","noun":"settings key","description":"Refuse to start when the [sandbox](\/docs\/en\/sandboxing) can't, instead of running unsandboxed","description_source":"docs","described_by":{"doc":"claude-code\/settings-reference","title":"All settings"},"presence":{"first_seen":null,"removed_in":null,"in_current_build":false,"newest_mined":"2.1.308","builds":0,"mined_builds":149,"first_cited":{"version":"2.1.248","released_at":"2026-08-27 20:35:36","spans":2}},"aliases":[],"entries":[{"version":"2.1.305","anchor":"windows-sandbox-allowlocalbinding-is-fixed-at-install-and-m","heading":"On Windows, the sandbox's local connection setting is fixed when the sandbox is installed","line":"On Windows, changing `sandbox.network.allowLocalBinding` now needs `\/sandbox install` and a restart, and Claude Code warns when they disagree","released_at":"2026-10-20 19:29:36","reason":"found in this 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