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
Degraded functionality for Claude Cowork on Windows
Official Claude incident record with affected components, status, timeline updates, and links back to relevant status checks.
Affected components
These are the official Claude components attached to this incident. Component data can help separate a web app issue from an API, Console, or Claude Code issue.
Official timeline
Updates are shown from the official Claude status incident record.
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.
