[BUG] Cowork VM starts but loses connection immediately — keep-alive ping timeouts on Windows 11

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?

Here's a draft bug report you can copy and paste:

Title: Cowork VM starts but loses connection immediately — keep-alive ping timeouts on Windows 11

Environment:

Claude Desktop version: 1.1.7053.0
OS: Windows 11
Install type: MSIX package
Network: Fios home internet, no VPN
Other: Microsoft 365 work account on personal machine, McAfee Security Scan Plus
What's wrong: Cowork fails to start with "VM connection timeout after 60 seconds." The VM boots and the API shows as reachable, but the internal connection drops immediately after startup with repeated keep-alive ping timeouts.

What I tried:

Fresh install of latest version this morning
Verified VirtualMachinePlatform and HypervisorPlatform are both Enabled
Verified CoworkVMService is Running
Force-killed all Claude processes and restarted
Full computer reboot
Key log entries from cowork_vm_node.log:

[VM:steps] load_swift_api completed (0ms)
[VM:start] Windows VM service configured
[VM:start] Startup complete, total time: 45387ms
[VM] Network status: CONNECTED
[VM] API reachability: REACHABLE
[warn] [Keepalive] Ping failed: Keep-alive ping timed out
[warn] [Keepalive] Ping failed: Keep-alive ping timed out
[error] RPC error -1: process already exited
Expected behavior: Cowork workspace loads and accepts input.

Go to https://github.com/anthropics/claude-code/issues/new, paste this in, and attach your actual log file from: C:\Users\shugh\AppData\Local\Packages\Claude_pzs8sxrjxfjjc\LocalCache\Roaming\Claude\logs\cowork_vm_node.log

Would you like help navigating the GitHub page to submit it?

What Should Happen?

I shoudl be able to log in

Error Messages/Logs

Error logs are too long, get error message Field can not be longer than 65536 characters

Steps to Reproduce

Cannot launch Claude cowork

Claude Model

Not sure / Multiple models

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Claude Desktop 1.1.7053.0 with Claude Code SDK version 2.1.76.

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_