[BUG]

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Environment:

OS: Windows 11 Home
Claude Desktop (latest version, auto-updated recently)
Not on a corporate network or VPN

What happened:
Cowork was working normally, then after what appears to be an auto-update, it crashes immediately on launch with no error message. Regular chat mode is unaffected. Reinstalling Claude Desktop did not resolve the issue.
Troubleshooting already attempted:

Downloaded and reinstalled Claude Desktop multiple times
Enabled Windows features via PowerShell (Admin): Containers and HypervisorPlatform
Installed Windows App Runtime 1.6
Attempted to manually create sessiondata.vhdx (failed — New-VHD not available on Windows 11 Home)
Attempted full cache clearance via PowerShell — blocked by file permission errors on ChromeNativeHost and other Claude files
Killed all Claude processes via Task Manager before cleanup attempts

What Should Happen?

Expected behavior: Cowork should launch as it did previously.
Note: New-VHD is unavailable on Windows 11 Home, suggesting Hyper-V module limitations may be a contributing factor, but since Cowork was previously functional on this same machine, this appears to be a regression introduced by a recent update.

Error Messages/Logs

Steps to Reproduce

Environment

Windows 11 Home
Claude Desktop (latest version)
No VPN or corporate network

Steps taken before resolution:

Ran PowerShell (x86, non-elevated) — failed with "requires elevation" error
Ran PowerShell as Administrator — enabled Containers and HypervisorPlatform features
Installed Windows App Runtime 1.6
Attempted New-VHD to create sessiondata.vhdx — failed, command not found on Windows 11 Home
Attempted to delete %APPDATA%\Claude and %LOCALAPPDATA%\Claude via PowerShell — blocked by ChromeNativeHost permission errors
Ran takeown and icacls to force ownership — still failed
Attempted manual deletion via File Explorer
Reinstalled Claude Desktop from https://claude.ai/download

Result: Cowork began working again after the above steps — likely a combination of the cleanup and a possible server-side fix from Anthropic.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

latest

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_