The fix takes 5 minutes if Windows cooperates. Here's what to do when it doesn't.
You open Claude Desktop, click on the Cowork tab, and instead of a workspace you get a message that says "Virtual Machine Platform not available." It tells you to enable the feature and restart your computer. You restart. Same error. You restart again. Same error.
Here's the weird part. Some people fix this in two minutes by toggling one Windows setting. Others have Hyper-V fully enabled, every virtualization feature turned on, and they're still stuck because of a detection bug in Claude Desktop that misclassifies their hardware as unsupported.
This post covers both paths. The quick fix that works for most people, and the deeper fixes for when Windows says virtualization is enabled but Claude refuses to believe it.
Why Claude Cowork needs a virtual machine at all
Claude Cowork runs your agent's workspace inside a sandboxed virtual machine on your local computer. This is a security decision. The VM isolates the agent's file access, network activity, and tool execution from the rest of your system, so a misbehaving agent can't accidentally (or maliciously) touch files outside its sandbox.
The tradeoff: your machine needs to support hardware virtualization, and Windows needs to have the right features turned on. If either condition isn't met, you get the error.
The "Virtual Machine Platform not available" error almost always means one of three things: the Windows feature isn't enabled, virtualization is disabled in your BIOS, or Claude's VM detection has a known bug. Fix them in that order.
Fix 1: Enable Virtual Machine Platform in Windows Features
This is the fix for the majority of people who see this error. Windows has the feature installed but it's not turned on by default.
Windows 11 and Windows 10 Pro/Enterprise/Education:
Open the Start menu, type "Turn Windows features on or off," and press Enter. In the list that appears, find and check these three items:
- Virtual Machine Platform (this is the one the error message specifically mentions)
- Windows Hypervisor Platform (the underlying hypervisor layer)
- Hyper-V (the full virtualization stack, includes management tools)
Click OK. Windows will install the features and ask you to restart. Restart.
If you prefer the command line, open PowerShell as Administrator and run:
dism.exe /online /enable-feature /featurename:VirtualMachinePlatform /all /norestart
dism.exe /online /enable-feature /featurename:HypervisorPlatform /all /norestart
dism.exe /online /enable-feature /featurename:Microsoft-Hyper-V-All /all /norestart
Then restart your computer.
To verify the features are actually enabled after restart, run this in PowerShell:
Get-WindowsOptionalFeature -Online -FeatureName VirtualMachinePlatform
If State shows Enabled, the feature is on. If it still shows Disabled after the restart, something deeper is wrong, and you need Fix 2.
Fix 2: Enable virtualization in your BIOS/UEFI
If Fix 1 didn't work, or if Windows wouldn't let you enable the features, your CPU's virtualization support is probably turned off at the hardware level. This is common on laptops that shipped with virtualization disabled by default.
How to check without entering BIOS: Open Task Manager (Ctrl+Shift+Esc), click the Performance tab, click CPU. Look for "Virtualization" in the bottom-right area. If it says "Disabled," you need to enable it in BIOS.
How to enter BIOS/UEFI: Restart your computer and press the BIOS key during boot. The key varies by manufacturer: F2 for most Dell and Lenovo laptops, F10 for HP, Del for most desktops, F12 for some Asus boards. If you're unsure, your manufacturer's website will have the specific key.
In BIOS, look for one of these settings (the name varies by manufacturer):
- Intel: "Intel Virtualization Technology" or "Intel VT-x" or "VT-x"
- AMD: "SVM Mode" or "AMD-V"
It's usually under Advanced, CPU Configuration, or Security. Enable it. Save and exit BIOS. Your computer will restart.
After the restart, go back to Fix 1 and enable the Windows features. They should work now.
If your BIOS doesn't have a virtualization option at all, your CPU may be too old to support it. Any Intel Core i-series from 4th generation (Haswell, 2013) onward supports VT-x. Any AMD Ryzen supports SVM. If you're on something older than that, Cowork won't work on this machine.
Fix 3: The "yukonSilver not supported" bug
Stay with me here, because this is the one that catches people who did everything right and are still stuck.
Multiple GitHub issues filed against Claude Desktop (#25136, #32004, #32837) report that even with Hyper-V fully enabled, Virtual Machine Platform enabled, and the CoworkVMService running correctly, Claude's VM detection classifies the system as "yukonSilver not supported" and enters a loop, deleting and rechecking for the VM bundle on every launch without ever initializing it.
"yukonSilver" is Claude's internal codename for its VM configuration on Windows. The bug is in the platform detection logic: it incorrectly classifies fully capable x64 Windows 11 Pro systems as unsupported.
How to tell if this is your problem: Navigate to %APPDATA%\Claude\logs\ and open cowork_vm_node.log. If you see repeated lines saying yukonSilver not supported (status=unsupported), you're hitting this specific bug.
This has been reported across Windows 11 Pro, Enterprise, and Education editions on builds 25H2 and later, with all virtualization features confirmed enabled via both the GUI and PowerShell verification.
What to try:
Check for conflicting hypervisors. If you previously had VirtualBox or VMware installed, traces of their hypervisor drivers can interfere with Windows' native Hyper-V even after uninstallation. Run systeminfo in a command prompt and look for the Hyper-V Requirements section. If it says "A hypervisor has been detected. Features required for Hyper-V will not be displayed," another hypervisor layer may still be active.
Try uninstalling and cleanly reinstalling Claude Desktop. Delete the %APPDATA%\Claude folder entirely before reinstalling, so the VM detection runs fresh without cached state from a previous failed attempt.
Update Claude Desktop to the latest version. This is a known, actively tracked bug across multiple GitHub issues, and Anthropic has been working on fixes to the platform detection logic. Running an older version means running older detection code.
If none of that works, the honest answer is that this is an Anthropic-side bug, not something you can fix with Windows settings. The workaround while waiting for a fix is to use Claude Cowork on a macOS machine if you have access to one (macOS uses Apple's Virtualization Framework instead of Hyper-V and doesn't hit this detection issue), or to use Claude Code via the terminal, which doesn't require the VM at all.
If your symptom is a missing Cowork tab rather than an explicit VM error, or the VM starts and then dies after a reboot, those are separate failure modes. Our full breakdown of Claude Cowork not working on Windows covers the CoworkVMService startup-type problem, the Host Compute Service stack, and the 172.16.0.0/24 network conflicts with Docker and VPNs.
What if you're on Windows Home?
This is where a lot of advice on the internet gets it slightly wrong. Windows Home does include Virtual Machine Platform and Windows Hypervisor Platform, so enabling those features can appear to succeed. What Home is missing is the full Hyper-V management stack, specifically the vmms (Virtual Machine Management) service that Cowork's VM depends on. Without it, the VM either fails silently or throws a mount error, even though the feature checkboxes looked fine.
The quickest way to confirm: open PowerShell and run Get-Service vmms. If the service isn't found, you're on Home and Cowork won't work without an edition upgrade.
One caveat worth knowing: Anthropic's downloadable Cowork readiness checker can falsely report "ready" on Windows 11 Home, because Windows 11 internally still reports its version as 10.0 and the checker misidentifies the OS (GitHub #50621). Trust Get-Service vmms over the checker.
Your options:
Upgrade to Windows Pro. Microsoft sells the upgrade for around $99 in the Microsoft Store. It's the only permanent fix for this limitation on Windows Home.
Use Claude Code instead of Cowork. Claude Code runs in your terminal without requiring a VM. You lose the visual Cowork workspace but keep all the AI coding capabilities.
Use Claude.ai chat. If your workflow doesn't require the sandboxed file-system access that Cowork provides, the web chat interface works on any OS without virtualization requirements.
If the idea of troubleshooting Windows virtualization settings, BIOS configurations, and VM detection bugs just to get an AI agent running sounds like the wrong use of your afternoon, that's a feeling we understand well. We built BetterClaw specifically so you never have to touch Hyper-V, Docker, or any local VM setup to run an AI agent. Everything runs on managed infrastructure.
No Hyper-V. No BIOS. No Windows edition restrictions.
Your agent runs on managed cloud infrastructure and deploys from any machine with a browser. Free forever, not a trial. Start free → No credit card · 25+ integrations · Deploy in ~60 seconds
Quick reference: the troubleshooting order
Step 1: Enable Virtual Machine Platform, Windows Hypervisor Platform, and Hyper-V in Windows Features. Restart.
Step 2: If that didn't work, check Task Manager for virtualization status. If disabled, enter BIOS and enable VT-x (Intel) or SVM Mode (AMD). Restart, then redo Step 1.
Step 3: If features are enabled but Claude still shows the error, check %APPDATA%\Claude\logs\cowork_vm_node.log for "yukonSilver not supported." If present, clean reinstall Claude Desktop and delete the %APPDATA%\Claude folder first.
Step 4: Run Get-Service vmms. If it's missing, you're on Windows Home — upgrade to Pro or use Claude Code/chat as alternatives.
If you're running into Claude rate limits on top of VM issues, that's a separate problem with a separate fix. And for teams managing agents across different machines where VM compatibility is inconsistent, our guide to cutting agent token costs covers the multi-provider routing approach that eliminates single-platform dependency entirely.
The honest takeaway
The Virtual Machine Platform error is one of those problems that's either a 5-minute fix or a 2-hour rabbit hole, with almost nothing in between. If you're in the 5-minute camp, the Windows Features toggle handles it. If you're in the 2-hour camp, you're probably hitting the yukonSilver detection bug, which is on Anthropic's side to fix.
Either way, the underlying pattern is worth noticing: running AI agents locally means depending on your specific hardware, your specific OS edition, and your specific BIOS settings all working together. Every one of those is a seam where something can break. If that dependency chain concerns you more than the problem du jour, give BetterClaw a try. Free plan with 1 agent and 500 credits a month. $49/month for Pro. No VMs required. No BIOS changes. No Windows edition restrictions. Your first agent deploys in about 60 seconds, on any machine with a browser.
Frequently Asked Questions
What does "Virtual Machine Platform not available" mean for Claude?
It means Claude Cowork can't start its sandboxed VM workspace because the Windows virtualization features it depends on aren't enabled or aren't detected. The fix is usually enabling Virtual Machine Platform and Hyper-V in Windows Features and restarting, but there's also a known detection bug where Claude misclassifies properly configured systems as unsupported.
How do I enable Hyper-V for Claude Cowork on Windows 11?
Open "Turn Windows features on or off" from the Start menu, check Virtual Machine Platform, Windows Hypervisor Platform, and Hyper-V, then restart your computer. If the checkboxes are greyed out, you may need to enable VT-x (Intel) or SVM Mode (AMD) in your BIOS first. Windows Home edition does not include the full Hyper-V stack and requires an upgrade to Pro.
How long does it take to fix the Claude VM error?
If the fix is just enabling Windows Features, about 5 minutes including the restart. If you need to enter BIOS to enable virtualization, add another 5 to 10 minutes. If you're hitting the yukonSilver detection bug, the fix may require waiting for an update from Anthropic, as it's a known issue in Claude Desktop's platform detection.
Can I use Claude Cowork on Windows Home?
Not currently. Windows Home includes Virtual Machine Platform and Windows Hypervisor Platform but lacks the vmms service that Cowork's VM requires, so the features can look enabled while the VM still fails. Run Get-Service vmms to confirm. Your options are upgrading to Windows Pro ($99 from Microsoft), using Claude Code via the terminal (no VM needed), or using the Claude.ai web chat interface.
Why does Claude Cowork need a virtual machine?
Cowork runs your agent's workspace inside a sandboxed VM to isolate its file access and tool execution from the rest of your system. This is a security measure that prevents an agent from accessing files or network resources outside its designated workspace, which matters when the agent is running autonomously and interacting with tools on your behalf.
