Windows Update Breaks Claude Desktop's Local File Access

The Windows cumulative update KB5124008 released on September 8 broke Claude Cowork's sandbox and prevented Claude Desktop from accessing local files, while Claude Code remained unaffected. Anthropic confirmed the issue, and uninstalling the patch is currently the only workaround.

2026-09-10 ~ 2026-09-11 · 3 related posts

• Windows update KB5124008 breaks Anthropic Cowork's sandbox shell; uninstall is the only fix — standard_deviant_Q · 2026-09-10
• Windows Update Breaks Claude Cowork's Local Command Execution; Microsoft Fix Incoming — ClaudeAI-mod-bot · 2026-09-10
• Windows September 8 update breaks Claude Desktop workspace file access; Claude Code unaffected — rentsby229 · 2026-09-11