[BUG] Cowork "Virtualization is not available" — HCS error 0x80370102 despite all Hyper-V components fully enabled (Windows 11)

[fernandocas-glitch]

Preflight Checklist

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

What's Wrong?

Preflight Checklist

• I have searched existing issues and this hasn't been reported with this specific log evidence
• This is a single bug report
• I am using the latest version of Claude Desktop

---

What's Wrong?

The Cowork tab permanently shows:

"Virtualization is not available — Claude's workspace requires Virtual Machine Platform, but the virtualization service isn't responding. Restart your computer to resolve this."

Restarting does not resolve the issue. The VM never initializes. I have identified the exact root cause from the service log.

---

Root Cause — Log Evidence

Log file: C:\ProgramData\Claude\Logs\cowork-service.log

2026/05/14 08:10:00 [HCS] HcsWaitForOperationResult returned: hr=0x80370102
{
  "Error": -2143878910,
  "ErrorMessage": "No se pudo iniciar la máquina virtual porque no se instaló una característica requerida.",
  "ErrorEvents": [{
    "Message": "No se puede crear el sistema 'cowork-vm-aa3e71f7' porque Hyper-V no está instalado en el host.",
    "Provider": "17103e3f-3c6e-4677-bb17-3b267eb5be57",
    "EventId": 11008
  }]
}

Claude Desktop is incorrectly reporting that Hyper-V is not installed, despite all components being fully enabled and running.

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System Verification — Everything Enabled

Component	Status
Microsoft-Hyper-V	✅ Enabled
Microsoft-Hyper-V-All	✅ Enabled
Microsoft-Hyper-V-Hypervisor	✅ Enabled
Microsoft-Hyper-V-Services	✅ Enabled
HypervisorPlatform	✅ Enabled
VirtualMachinePlatform	✅ Enabled
CoworkVMService	✅ Running / Automatic
vmms (Hyper-V VM Management)	✅ Running / Automatic
bcdedit hypervisorlaunchtype	✅ Auto
VirtualBox VMs	✅ Running without issues
systeminfo Hyper-V	✅ "A hypervisor has been detected"

VirtualBox is installed and running virtual machines successfully, confirming that hardware virtualization (AMD-V / Intel VT-x) is fully functional at the CPU level.

---

Steps to Reproduce

1. Install Claude Desktop on Windows 11
2. Enable Hyper-V, Virtual Machine Platform, and Windows Hypervisor Platform
3. Verify all services are running (CoworkVMService, vmms)
4. Launch Claude Desktop and navigate to the Cowork tab
5. Observe "Virtualization is not available" error immediately
6. Check C:\ProgramData\Claude\Logs\cowork-service.log — HCS returns error 0x80370102

Expected Behavior

Cowork detects that all Hyper-V components are enabled and successfully initializes the VM workspace.

Actual Behavior

HCS (Host Compute Service) call fails with error 0x80370102. Claude Desktop reports Hyper-V is not installed despite it being fully enabled. The VM never initializes.

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Environment

• Claude Desktop version: Latest (installed via .exe installer)
• OS: Windows 11
• Subscription: Claude Pro
• HCS Error code: 0x80370102

---

Notes

This appears to be the same issue reported in #27316, #27420, #29887, #32004, #37265, #42227, #45715, #51813.

The key difference in this report is the exact HCS error from the service log, which pinpoints the failure to Claude Desktop's VM initialization call rather than any system configuration issue.

I am happy to provide additional logs, run diagnostic commands, or collaborate with the team to help identify the root cause and test any fixes.

What Should Happen?

Cowork should detect that all Hyper-V components are enabled and successfully initialize the VM workspace.

Error Messages/Logs

HCS error: 0x80370102
"No se puede crear el sistema 'cowork-vm-aa3e71f7' porque Hyper-V no está instalado en el host."

Steps to Reproduce

Install Claude Desktop on Windows 11 with all Hyper-V components enabled
Open Claude Desktop → Cowork tab
Error appears immediately. Check cowork-service.log for HCS error 0x80370102

Claude Model

Not sure / Multiple models

Is this a regression?

No, this never worked

Last Working Version

No response

Claude Code Version

N/A — This bug is in Claude Desktop (Cowork tab), not Claude Code CLI. Claude Desktop latest version, installed via .exe installer from claude.ai/download

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

Same issue as #27316, #27420, #29887, #32004, #37265, #42227, #45715, #51813. This report includes the exact HCS error code from cowork-service.log. Happy to collaborate with the team to test fixes.

[github-actions]

Found 3 possible duplicate issues:

1. [BUG] Cowork shows "Virtualization is not enabled" on Windows 10 Pro despite Hyper-V fully enabled #27316
2. [BUG] Cowork "Virtualization is not available" on Windows 11 Pro 25H2 — all virtualization features enabled, VM never initializes #51813
3. [BUG] Cowork shows "Virtualization is not enabled" on Windows 11 despite Hyper-V fully enabled (Lenovo ThinkPad) #27420

This issue will be automatically closed as a duplicate in 3 days.

• If your issue is a duplicate, please close it and 👍 the existing issue instead
• To prevent auto-closure, add a comment or 👎 this comment

🤖 Generated with Claude Code

[fernandocas-glitch]

This is not a duplicate. While the symptom is the same as #27316, #51813, and #27420, this report provides something the others do not: the exact HCS error code (0x80370102) extracted directly from cowork-service.log, which pinpoints the failure to Claude Desktop's VM initialization call.
All other reports describe the symptom. This report identifies the root cause. Please keep this open as it provides actionable technical evidence for the engineering team.

[github-actions]

Closing for now — inactive for too long. Please open a new issue if this is still relevant.

[DreikalCC]

Independent reproduction of this issue, with all host-level virtualization prerequisites confirmed present.

Environment

• OS: Windows 10 Pro, build 19045 (22H2)
• Motherboard: MSI, Intel VT-x confirmed enabled in BIOS/UEFI
• systeminfo Hyper-V Requirements, all four report Yes: VM Monitor Mode Extensions, Virtualization Enabled In Firmware, Second Level Address Translation, Data Execution Prevention Available

Steps to reproduce

1. On a Windows 10 22H2 (build 19045) machine with VT-x enabled in firmware and all four Hyper-V requirements confirmed via systeminfo, open Claude Desktop → Cowork.
2. Attempt any action that requires the sandboxed shell tool.
3. Observe: "Workspace unavailable. The isolated Linux environment failed to start (HYPERVISOR_VIRT_DISABLED)."

Notes
File tools (Read/Write/Edit) continue to function normally - only the sandboxed shell is affected - which suggests the failure is in Claude's own VM/HCS initialization path rather than a genuine host-level virtualization gap. Every user-controllable fix has been exhausted on this machine (BIOS toggle, Windows Features, full shutdown/restart, Core Isolation toggle), matching the pattern already described here and in the linked duplicates. Worth escalating past "not planned" given multiple independent reporters on the same OS build.