[BUG] Cowork "Virtualization is not enabled" error despite hypervisor active — regression on Windows 11 Home 25H2
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?
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<!--StartFragment--><p class="font-claude-response-body break-words whitespace-normal leading-[1.7]">Cowork displays <strong>"Virtualization is not enabled. Claude's workspace requires hardware virtualization (Hyper-V)"</strong> error, despite all virtualization features being confirmed active and working correctly at the system level.</p>
<p class="font-claude-response-body break-words whitespace-normal leading-[1.7]"><strong>This is a regression</strong> — Cowork was working fine on this exact same Windows 11 Home configuration until a few days ago. The issue started appearing after a recent Claude Desktop update.</p>
<h4 class="text-text-100 mt-2 -mb-1 text-base font-bold">System verification confirms virtualization is fully operational:</h4>
<div class="overflow-x-auto w-full px-2 mb-6">
Check | Result
-- | --
Task Manager → Virtualization | ✅ Enabled
vmcompute service | ✅ Running
vmms service | ✅ Running (Automatic)
systeminfo | "A hypervisor has been detected. Features required for Hyper-V will not be displayed."
VirtualMachinePlatform | ✅ Enabled
HypervisorPlatform | ✅ Enabled
Microsoft-Windows-Subsystem-Linux | ✅ Enabled
WSL2 + Ubuntu | ✅ Installed and working
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<h4 class="text-text-100 mt-2 -mb-1 text-base font-bold">Troubleshooting already attempted (all failed):</h4>
<ol class="[li_&]:mb-0 [li_&]:mt-1 [li_&]:gap-1 [&:not(:last-child)_ul]:pb-1 [&:not(:last-child)_ol]:pb-1 list-decimal flex flex-col gap-1 pl-8 mb-3">
<li class="whitespace-normal break-words pl-2">Disabled and re-enabled all virtualization features (VirtualMachinePlatform, HypervisorPlatform, WSL) via DISM</li>
<li class="whitespace-normal break-words pl-2">Reinstalled WSL2 with Ubuntu distribution</li>
<li class="whitespace-normal break-words pl-2">Uninstalled and reinstalled Claude Desktop</li>
<li class="whitespace-normal break-words pl-2"><strong>Full OS reset (Remove Everything)</strong> — performed a complete Windows reset, reinstalled everything from scratch</li>
<li class="whitespace-normal break-words pl-2">Multiple reboots throughout the process</li>
</ol>
<p class="font-claude-response-body break-words whitespace-normal leading-[1.7]"><strong>None of these resolved the issue.</strong> The error persists even after a full OS reset, which strongly suggests this is a Claude Desktop app-side detection bug, not a system configuration issue.</p><!--EndFragment-->
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What Should Happen?
Cowork should detect the active hypervisor and start the workspace successfully, as it did before the recent update.
Error Messages/Logs
"Virtualization is not enabled. Claude's workspace requires hardware virtualization (Hyper-V)."
Note: Could not locate cowork_vm_node.log at %APPDATA%\Claude\logs\ — the Claude folder does not exist at that path. Log directory location for MSIX installs may differ.Steps to Reproduce
Install Claude Desktop (latest version) on Windows 11 Home 25H2
Ensure all virtualization features are enabled and verified working
Open Claude Desktop
Switch to Cowork tab
Observe: "Virtualization is not enabled" error appears immediately
Claude Model
Sonnet (default)
Is this a regression?
Yes, this worked in a previous version
Last Working Version
_No response_
Claude Code Version
Claude Desktop (latest MSIX install from claude.ai/download). This is Cowork on Claude Desktop, not Claude Code CLI.
Platform
Anthropic API
Operating System
Windows
Terminal/Shell
PowerShell
Additional Information
This is NOT a system virtualization issue — all system-level checks confirm virtualization is active and functional.
This is a regression — the same hardware + OS combination was running Cowork successfully before the recent update.
A full OS reset was performed (Remove Everything), ruling out any corrupted system state.
Regular Chat mode works perfectly in the same Claude Desktop app — only Cowork is affected.
The app appears to have a faulty virtualization detection mechanism that fails on Windows 11 Home despite the hypervisor being active.
Possibly related (but different symptoms): #24918, #25241, #25663
13 Comments
Found 3 possible duplicate issues:
This issue will be automatically closed as a duplicate in 3 days.
🤖 Generated with Claude Code
Same issue here. Dell Precision 7770, Windows Pro (domain-joined), Intel 12th Gen, x64.
From cowork_vm_node.log:
Hyper-V: Enabled, VT-x/VT-d: Enabled in BIOS, CoworkVMService: Running.
Claude Desktop v1.1.3918 (a4b368).
Also a regression — Cowork was working previously on this same system.
Identical to #25136.
Same issue on:
Windows 10 Education, Hyper-V enabled, virtualization enabled in BIOS, still showing "Virtualization is not enabled" error.
Same issue on Windows 11 Pro, had been working perfectly last night.
Same problem on Windows 11 Pro. Everything enabled. Hyper-V is enabled.
I have this issue can you investigate if it is indeed a bug or there is anything I can do?
Environment:
OS: Windows 11 Pro 25H2 (Build 26200.7462) — received via standard Windows Update, not Insider Programme
Hardware: Dell Latitude 7400 (physical machine, confirmed not a VM)
Installer: Claude Setup.exe (direct download from claude.ai/download)
Windows Features enabled:
Microsoft-Hyper-V-All ✅
HypervisorPlatform ✅
VirtualMachinePlatform ✅
WSL2 installed with Ubuntu ✅
Services running:
vmms (Running, Automatic)
vmcompute (Running, Manual)
hns (Running, Manual)
Relevant log output from cowork_vm_node.log:
2026-02-21 10:21:44 [info] [cleanupVMBundleIfUnsupported] yukonSilver not supported (status=unsupported), checking for stale bundle... 2026-02-21 10:22:37 [warn] [startVM] VM not supported (win32/x64), skipping
Error shown in UI:
"Virtualization is not enabled. Claude's workspace requires hardware virtualization (Hyper-V). Enable virtualization in your computer's BIOS/UEFI settings, then restart."
This error is misleading — hardware virtualization is confirmed enabled and all required features are active. The issue appears to be yukonSilver incorrectly flagging this win32/x64 environment as unsupported despite full Hyper-V support being present.
Same issue here
Confirm same regression on Windows with Claude Desktop 1.1.3918.0: Cowork UI says "Virtualization is not enabled", but Hyper-V/WSL are enabled and working. Logs show Cowork incorrectly gates the VM as unsupported and skips startup.
Env
Key log lines (cowork_vm_node.log)
(repeats continuously even after reboot)
Bundle reset attempt
Rollback not possible
Also seeing multiple similar reports (e.g., #27354 ).
Closing as duplicate of #27316 which was very rapidly fixed in the v1.1.3963 release
Environment
Background / Prior Issue
Previously affected by the API unreachability bug tracked in #24918. That issue was closed, but a new error has since appeared. The hardware and OS configuration have not changed between the two issues.
Current Error
Cowork tab now displays: "Virtualization is not enabled. Claude's workspace requires hardware virtualization (Hyper-V). Enable virtualization in your computer's BIOS/UEFI settings, then restart."
This error appears to be a false positive — virtualization has not been disabled and no system changes were made between the prior working state and this error appearing.
What's confirmed working on this machine
Pattern worth flagging
This is the second distinct Cowork failure on the same machine and OS in under two weeks — first the API unreachability bug, now faulty virtualization detection. Both issues appeared after app updates without any change to the underlying hardware or OS configuration. This may suggest the app's preflight detection logic is fragile on Windows 11 Home specifically.
Request
Please confirm whether 1.1.3963 addresses this detection issue for Windows 11 Home users, or whether a separate fix is needed.
Per previous message, the incorrect detection was a bug fixed v1.1.3963
Windows 11 Home is fully supported and known to be working, any issues facing Windows 11 Home users should be reported separately once validated to be occurring on the latest Claude Desktop release
Bug still present on Windows 11 Pro (x64)
Hyper-V is fully enabled and running. Verified via
systeminfo— all four Hyper-V requirements show "Yes." Appliedbcdedit /set hypervisorlaunchtype auto, restarted multiple times. The virtualization service is responding normally for other applications.Despite all of this, Claude Desktop still shows: "Virtualization is not available — Claude's workspace requires Hyper-V, but the virtualization service isn't responding."
This appears to be a detection bug in Claude Desktop itself, not a system configuration issue. Please prioritize fixing this — it's blocking Cowork usage entirely.
System info:
This issue has been automatically locked since it was closed and has not had any activity for 7 days. If you're experiencing a similar issue, please file a new issue and reference this one if it's relevant.