[BUG] Missing HCS services: vfpext — persists after DISM/SFC repair and Hyper-V re-enable (Windows 11 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?

Here's a draft you can copy directly into a new issue at github.com/anthropics/claude-code/issues/new:

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Title: Missing HCS services: vfpext — persists after DISM/SFC repair and Hyper-V re-enable (Windows 11 Pro)

What's wrong?
Cowork in Claude Desktop shows "Missing HCS services: vfpext" and the Cowork toggle/tab remains disabled. The vfpext.sys driver file does not exist on disk, and standard Windows servicing repair does not restore it.

Environment

• OS: Windows 11 Pro
• Plan: Pro
• Claude Desktop: [Version 1.22209.0 (77c938)]

Steps to reproduce

1. Open Claude Desktop
2. Click the Cowork toggle
3. Error shown: "Missing HCS services: HNS, vmcompute, vfpext"
4. Cowork remains disabled

What I've already tried (no effect on vfpext)

• Enabled Microsoft-Hyper-V, VirtualMachinePlatform, and Containers optional features, rebooted
• Test-Path C:\Windows\System32\drivers\vfpext.sys → returns False
• DISM /Online /Cleanup-Image /ScanHealth → completed
• DISM /Online /Cleanup-Image /RestoreHealth → completed successfully, no effect
• sfc /scannow → completed, no unresolved integrity violations
• Full disable/re-enable cycle of Hyper-V feature, rebooted each time — no effect
• Get-Service vfpext → "Cannot find any service with service name 'vfpext'"

Expected behavior
Either the vfpext driver installs correctly via the standard Hyper-V/VMP feature enable + DISM repair path, or Cowork provides a clearer diagnostic/remediation path when this specific driver is missing but the rest of the HCS stack (HNS, vmcompute) is present.

Additional notes
Other users have reported this same specific symptom (driver missing, not just unregistered) even after a full in-place Windows repair install from ISO. This may point to a Windows servicing edge case rather than something fixable purely via feature toggles, but flagging here since it's blocking Cowork specifically.

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What Should Happen?

Either the vfpext driver installs correctly via the standard Hyper-V/VMP feature enable + DISM repair path, or Cowork provides a clearer diagnostic/remediation path when this specific driver is missing but the rest of the HCS stack (HNS, vmcompute) is present.

Error Messages/Logs

- Enabled `Microsoft-Hyper-V`, `VirtualMachinePlatform`, and `Containers` optional features, rebooted
- `Test-Path C:\Windows\System32\drivers\vfpext.sys` → returns `False`
- `DISM /Online /Cleanup-Image /ScanHealth` → completed
- `DISM /Online /Cleanup-Image /RestoreHealth` → completed successfully, no effect
- `sfc /scannow` → completed, no unresolved integrity violations
- Full disable/re-enable cycle of Hyper-V feature, rebooted each time — no effect
- `Get-Service vfpext` → "Cannot find any service with service name 'vfpext'"

Steps to Reproduce

1. Open Claude Desktop
2. Click the Cowork toggle
3. Error shown: "Missing HCS services: HNS, vmcompute, vfpext"
4. Cowork remains disabled

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Version 1.22209.0 (77c938)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

Other users have reported this same specific symptom (driver missing, not just unregistered) even after a full in-place Windows repair install from ISO. This may point to a Windows servicing edge case rather than something fixable purely via feature toggles, but flagging here since it's blocking Cowork specifically.

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