[BUG] Virtualization not enabled - Win11 Pro

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 not enabled" despite correct Hyper-V configuration — yukonSilver not supported (win32/x64)

System: HP Victus Gaming Laptop 2023, Intel Core i5 x64, 32GB RAM, Windows 11 Pro
Claude Plan: Pro
Claude Desktop Version: Latest (downloaded February 2026)
Problem: CoWork permanently shows "Hardware virtualization is not enabled" despite all settings being correctly configured.

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Troubleshooting steps completed (none resolved the issue):

1. BIOS Settings ✅

• Virtualization Technology set to Enabled in BIOS (was already active)

2. Windows Features enabled ✅

Enabled the following under "Turn Windows features on or off":

• Hyper-V (fully, including all sub-features)
• Virtual Machine Platform
• Windows Hypervisor Platform

3. Memory Integrity disabled ✅

• Settings → Device Security → Core Isolation Details → Memory Integrity Off

4. Multiple full restarts ✅

5. Claude Desktop fully uninstalled, restarted, reinstalled ✅

6. Cache cleared ✅

• Help → Troubleshooting → Clear cache and restart

7. Bitdefender completely disabled ✅

• All protection features paused, then Claude launched as Administrator

8. Claude launched as Administrator ✅

9. Hyper-V status confirmed via PowerShell (as Administrator) ✅

Get-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V
→ State: Enabled

10. systeminfo verified ✅

Hyper-V Requirements: A hypervisor has been detected. Features required for Hyper-V will not be displayed.

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Root cause — found in logs

Log file location:

C:\Users\[USERNAME]\AppData\Local\Packages\Claude_pzs8sxrjxfjjc\LocalCache\Roaming\Claude\logs\cowork_vm_node.log

Log content (repeating continuously):

[info] [cleanupVMBundleIfUnsupported] yukonSilver not supported (status=unsupported), checking for stale bundle...
[warn] [startVM] VM not supported (win32/x64), skipping

→ CoWork is incorrectly classifying the system as unsupported, even though Windows 11 Pro x64 with Hyper-V should be a fully supported configuration.

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Anthropic Support response

"The 'yukonSilver not supported' error appears to be a compatibility check failure where CoWork incorrectly classifies your system as unsupported. The issue is likely related to an ongoing system-wide incident ('Intermittent errors in skills-related functionality') that has been under investigation since February 17th."

Status page: https://stspg.io/lncvg79zrr5w

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Current status

According to support this is a known bug on Anthropic's side — no workaround available from the user side. Has anyone else encountered this issue or found a fix?

What Should Happen?

CoWork should recognize Windows 11 Pro x64 with Hyper-V enabled as a supported platform and successfully start the virtual machine. The yukonSilver VM configuration should not be classified as "unsupported" on a fully capable x64 system with all required virtualization features enabled (Hyper-V, Virtual Machine Platform, Windows Hypervisor Platform).

Error Messages/Logs

Steps to Reproduce

Install Claude Desktop (latest version) on Windows 11 Pro x64
Enable Hyper-V, Virtual Machine Platform, and Windows Hypervisor Platform via Windows Features
Disable Memory Integrity (Settings → Device Security → Core Isolation)
Restart the computer
Open Claude Desktop and navigate to the Cowork tab
Observe the error: "Hardware virtualization is not enabled"
Check the log file at:
C:\Users\[USERNAME]\AppData\Local\Packages\Claude_pzs8sxrjxfjjc\LocalCache\Roaming\Claude\logs\cowork_vm_node.log
Observe repeated entries: yukonSilver not supported (status=unsupported) and [startVM] VM not supported (win32/x64), skipping

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

N/A — Using Claude Desktop App (not Claude Code CLI). Version: latest, downloaded February 21, 2026.

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_