[BUG] Cowork shows "Virtualization is not available" on Windows 11 Pro despite Hyper-V fully enabled and services running**

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?

[BUG] Cowork shows "Virtualization is not available" on Windows 11 Pro despite Hyper-V fully enabled and services running

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report
• [x] I am using the latest version of Claude Desktop

What's Wrong?

Cowork displays "Virtualization is not available — Claude's workspace requires Hyper-V, but the virtualization service isn't responding" despite all Hyper-V prerequisites being fully configured and verified.

System Information

• OS: Windows 11 Pro (Build 26200.7922)
• Claude Desktop version: Latest
• Install type: Standard installer

Verification Checklist

| Check | Result |
|---|---|
| vmcompute service | ✅ Running |
| vmms service | ✅ Running |
| Hyper-V (DISM) | ✅ Enabled |
| Virtual Machine Platform | ✅ Enabled |
| Windows Hypervisor Platform | ✅ Enabled |
| bcdedit hypervisorlaunchtype | ✅ Set to Auto |
| vmms.exe exists | ✅ Confirmed |
| Restarted computer | ✅ Multiple times |

Steps to Reproduce

1. Install Claude Desktop on Windows 11 Pro
2. Enable all Hyper-V features via DISM and optionalfeatures
3. Confirm all services (vmcompute, vmms) are Running
4. Open Claude Desktop and navigate to Cowork tab
5. Observe error: "Virtualization is not available"

Expected Behavior

Cowork should detect that Hyper-V is active and all required services are running, and initialize the workspace successfully.

Actual Behavior

Cowork shows the error and never attempts to start the VM, despite all system-level checks confirming virtualization is fully operational.

Additional Notes

This appears to be a detection bug on the app side, not a system configuration issue. All system-level verifications confirm Hyper-V is properly installed and running.

What Should Happen?

cowork should work ? not sure. i get Virtualization is not available

Error Messages/Logs

Steps to Reproduce

Install Claude Desktop on Windows 11 Pro
Open Claude Desktop and navigate to the Cowork tab
Observe error: "Virtualization is not available — Claude's workspace requires Hyper-V, but the virtualization service isn't responding"
Run bcdedit /set hypervisorlaunchtype auto — succeeds
Enable Hyper-V, Virtual Machine Platform, and Windows Hypervisor Platform via optionalfeatures — succeeds
Run DISM /Online /Enable-Feature /FeatureName:Microsoft-Hyper-V /All /LimitAccess — succeeds
Restart computer
Confirm vmcompute and vmms are both Running
Confirm vmms.exe exists at C:\Windows\System32\vmms.exe
Reopen Claude Desktop → Cowork tab still shows the same error

Claude Model

Not sure / Multiple models

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude 1.1.5749 (ecf3d9) 2026-03-08T18:23:37.000Z

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_