# Claude: Degraded functionality for Claude Cowork on Windows

- Impact (vendor’s label): major
- Status: resolved
- Started: 2026-09-10 15:54 UTC · Resolved: 2026-09-14 19:14 UTC · Duration: 4 d
- Updates: 2 · Affected components: Claude Cowork
- [Vendor status page: https://stspg.io/5yp3rhhztm30](https://stspg.io/5yp3rhhztm30)
- [Company: Claude](https://rewindex.com/company/claude.md)

## Summary

Claude Cowork on Windows could not run local commands after a September 8 Windows update blocked workspace access to the computer’s drive; chat and file reading/editing mostly worked. The major incident ran from 2026-09-10 15:54 UTC to 2026-09-14 19:14 UTC (4 days 3 h), resolved by Microsoft’s September 14 Windows update. _(machine-written, sol)_
## Timeline of updates

- **identified** 2026-09-10 15:54 UTC: A Windows update released September 8 has left Claude Cowork on Windows unable to run local commands, because its workspace can no longer reach your computer's drive. For most users, chat and file reading and editing still work. There's no in-app workaround yet, and restarting or reinstalling won't help. Microsoft has developed a fix and is working to release it. We'll post an update when we have more to share.
- **resolved** 2026-09-14 19:14 UTC: This issue has been resolved. Microsoft has released a September 14 Windows update that fixes it: https://support.microsoft.com/en-us/servicing/os/windows-11/2026/09/kb5129195-windows-11-24h2-25h2-security-update

## Rewindex changes for this incident

- 2026-09-10 15:54 UTC: [Major incident: Degraded functionality for Claude Cowork on Windows](https://rewindex.com/change/i0e14d7c78a9105.md)


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Canonical: https://rewindex.com/company/claude/incidents/r1pqn1kb4hvk · Markdown: https://rewindex.com/company/claude/incidents/r1pqn1kb4hvk.md · JSON: https://rewindex.com/api/v1/companies/claude/incidents/r1pqn1kb4hvk · Generated 2026-10-18T09:59:51.100Z