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.

Claude Cowork

Official timeline

Updates are shown from the official Claude status incident record.

resolved

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

identified

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.