[BUG]

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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PS C:\WINDOWS\system32> Get-Content "$env:APPDATA\Claude\logs\cowork_vm_node.log" -Tail 50
2026-02-17 20:44:06 [info] Downloading rootfs.vhdx...
2026-02-17 20:44:07 [info] [VM:start] Beginning startup, bundlePath=C:\Users\User\AppData\Roaming\Claude\vm_bundles\claudevm.bundle
2026-02-17 20:44:07 [info] [VM:start] Bundle version: 0ae58222a1f34cf74c74ce47cc717a82a4eb0f25
2026-02-17 20:44:07 [info] [VM:start] VM instance ID: 15e9e37a-dcfc-4770-a76e-ef606b611487
2026-02-17 20:44:07 [info] [VM:steps] download_and_sdk_prepare started
2026-02-17 20:44:07 [info] [downloadVM] Download already in progress, waiting...
2026-02-17 20:47:35 [info] rootfs.vhdx.zst checksum validated
2026-02-17 20:47:35 [info] [downloadVM] Saved compressed rootfs.vhdx to cache
2026-02-17 20:47:35 [info] [Bundle:status] vmlinuz missing
2026-02-17 20:47:35 [info] [warm] No warm file found for vmlinuz at current version
2026-02-17 20:47:35 [info] [cache] No cached compressed file for vmlinuz
2026-02-17 20:47:35 [info] vmlinuz not found, downloading...
2026-02-17 20:47:35 [info] Downloading vmlinuz...
2026-02-17 20:47:36 [info] vmlinuz.zst checksum validated
2026-02-17 20:47:36 [info] [downloadVM] Saved compressed vmlinuz to cache
2026-02-17 20:47:36 [info] [Bundle:status] initrd missing
2026-02-17 20:47:36 [info] [warm] No warm file found for initrd at current version
2026-02-17 20:47:36 [info] [cache] No cached compressed file for initrd
2026-02-17 20:47:36 [info] initrd not found, downloading...
2026-02-17 20:47:36 [info] Downloading initrd...
2026-02-17 20:47:56 [info] initrd.zst checksum validated
2026-02-17 20:47:56 [info] [downloadVM] Saved compressed initrd to cache
2026-02-17 20:47:56 [info] All files ready in C:\Users\User\AppData\Roaming\Claude\vm_bundles\claudevm.bundle
2026-02-17 20:47:56 [info] [VM:steps] download_and_sdk_prepare completed (229175ms)
2026-02-17 20:47:56 [info] [VM:steps] load_swift_api started
2026-02-17 20:47:56 [info] [VM:steps] load_swift_api completed (0ms)
2026-02-17 20:47:56 [info] [Callbacks] Initializing VM event callbacks...
2026-02-17 20:47:56 [info] [Callbacks] VM event callbacks initialized
2026-02-17 20:47:56 [info] [VM:start] Copying smol-bin.x64.vhdx to bundle: C:\Program Files\WindowsApps\Claude_1.1.3363.0_x64__pzs8sxrjxfjjc\app\resources\smol-bin.x64.vhdx -> C:\Users\User\AppData\Roaming\Claude\vm_bundles\claudevm.bundle\smol-bin.vhdx
2026-02-17 20:47:56 [info] [VM:start] smol-bin.x64.vhdx copied successfully
2026-02-17 20:47:56 [info] [VM:start] Configuring Windows VM service...
2026-02-17 20:47:56 [info] [VM:start] Windows VM service configured
2026-02-17 20:48:04 [info] [VM] Network status: NOT_CONNECTED
2026-02-17 20:48:04 [info] [VM:network] Not connected, will show error in 30000ms if not resolved
2026-02-17 20:48:04 [info] [VM:steps] sdk_install started
2026-02-17 20:48:04 [info] [VM:start] Installing SDK: subpath=AppData/Roaming/Claude/claude-code-vm, version=2.1.41
2026-02-17 20:48:04 [info] [VM] Network status: CONNECTED
2026-02-17 20:48:05 [info] [VM] API reachability: REACHABLE
2026-02-17 20:48:06 [info] [VM:steps] sdk_install completed (1374ms)
2026-02-17 20:48:06 [info] [VM:start] Startup complete, total time: 238856ms
2026-02-17 20:48:06 [info] [Keepalive] Starting (interval=2000ms)
2026-02-18 16:43:40 [info] [warm] Fetching VM hash for version 1.1.3541
2026-02-18 16:43:40 [info] [warm] VM hash for version 1.1.3541: 0ae58222a1f34cf74c74ce47cc717a82a4eb0f25
2026-02-18 16:43:40 [info] [warm] VM SHA matches current version, skipping
2026-02-23 13:23:37 [info] [cleanupVMBundleIfUnsupported] yukonSilver not supported (status=unsupported), checking for stale bundle...
2026-02-23 13:23:37 [info] [deleteVMBundle] Deleting reinstall files from C:\Users\User\AppData\Roaming\Claude\vm_bundles\claudevm.bundle
2026-02-23 13:23:37 [info] [deleteVMBundle] Reinstall files deleted (sessiondata.img and rootfs.img.zst preserved)
2026-02-23 13:33:20 [info] [cleanupVMBundleIfUnsupported] yukonSilver not supported (status=unsupported), checking for stale bundle...
2026-02-23 13:33:20 [info] [deleteVMBundle] Deleting reinstall files from C:\Users\User\AppData\Roaming\Claude\vm_bundles\claudevm.bundle
2026-02-23 13:33:20 [info] [deleteVMBundle] Reinstall files deleted (sessiondata.img and rootfs.img.zst preserved)
PS C:\WINDOWS\system32> Get-WindowsOptionalFeature -Online -FeatureName Virtual

FeatureName : VirtualMachinePlatform
DisplayName : Virtual Machine Platform
Description : Enables platform support for virtual machines
RestartRequired : Possible
State : Enabled
CustomProperties :

FeatureName : HyperV-KernelInt-VirtualDevice
DisplayName : Microsoft NT Kernel Integration Virtual Device
Description : Microsoft NT Kernel Integration Virtual Device
RestartRequired : Possible
State : Disabled
CustomProperties :

PS C:\WINDOWS\system32> Get-Service CoworkVMService

Status Name DisplayName
------ ---- -----------
Running CoworkVMService Claude

PS C:\WINDOWS\system32> sc.exe qc CoworkVMService
[SC] QueryServiceConfig SUCCESS

SERVICE_NAME: CoworkVMService
TYPE : 210 WIN32_PACKAGED_PROCESS
START_TYPE : 2 AUTO_START
ERROR_CONTROL : 0 IGNORE
BINARY_PATH_NAME : "C:\Program Files\WindowsApps\Claude_1.1.3541.0_x64__pzs8sxrjxfjjc\app\resources\cowork-svc.exe"
LOAD_ORDER_GROUP :
TAG : 0
DISPLAY_NAME : Claude
DEPENDENCIES : staterepository
SERVICE_START_NAME : LocalSystem
PS C:\WINDOWS\system32> Get-NetNat
PS C:\WINDOWS\system32> Get-HnsNetwork | Where-Object { $_.Name -eq "cowork-vm-nat" }

ActivityId : 5E3389AE-2140-43A4-9D9A-75112F2B788B
AdditionalParams :
CurrentEndpointCount : 0
Extensions : {@{Id=F74F241B-440F-4433-BB28-00F89EAD20D8; IsEnabled=False; Name=Microsoft Azure VFP Switch
Filter Extension}, @{Id=E7C3B2F0-F3C5-48DF-AF2B-10FED6D72E7A; IsEnabled=False; Name=Microsoft
Windows Filtering Platform}, @{Id=430BDADD-BAB0-41AB-A369-94B67FA5BE0A; IsEnabled=True;
Name=Microsoft NDIS Capture}}
Flags : 8
Health : @{LastErrorCode=0; LastUpdateTime=134163487281952838}
ID : 4F257814-6DDB-4472-B10E-9FBF87D013A3
IPv6 : False
LayeredOn : 6E8F8CF2-B5C3-4682-B657-32608EDB6400
MacPools : {@{EndMacAddress=00-15-5D-1C-8F-FF; StartMacAddress=00-15-5D-1C-80-00}}
MaxConcurrentEndpoints : 0
Name : cowork-vm-nat
NatName : NAT9C38C466-7F33-45D6-BFBE-EF80E4C01B11
Policies : {@{Type=VLAN; VLAN=1}}
State : 1
Subnets : {@{AdditionalParams=; AddressPrefix=172.16.0.0/24; Flags=0; GatewayAddress=172.16.0.1;
Health=; ID=860C258C-5C67-4263-9BA4-1F8C9C01BD14; IpSubnets=System.Object[]; ObjectType=5;
Policies=System.Object[]; State=0}}
SwitchGuid : 4F257814-6DDB-4472-B10E-9FBF87D013A3
TotalEndpoints : 0
Type : NAT
Version : 68719476736
Resources : @{AdditionalParams=; AllocationOrder=2; Allocators=System.Object[];
CompartmentOperationTime=0; Flags=0; Health=; ID=5E3389AE-2140-43A4-9D9A-75112F2B788B;
PortOperationTime=0; State=1; SwitchOperationTime=0; VfpOperationTime=0;
parentId=B8D04222-624F-48DD-A3D4-82BD879A18C5}

PS C:\WINDOWS\system32> New-NetNat -Name "cowork-vm-nat" -InternalIPInterfaceAddressPrefix "172.16.0.0/24"
New-NetNat : You were not connected because a duplicate name exists on the network. If joining a domain, go to System
in Control Panel to change the computer name and try again. If joining a workgroup, choose another workgroup name.
At line:1 char:1

• New-NetNat -Name "cowork-vm-nat" -InternalIPInterfaceAddressPrefix "1 ...
• ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
• CategoryInfo : NotSpecified: (MSFT_NetNat:root/StandardCimv2/MSFT_NetNat) [New-NetNat], CimException
• FullyQualifiedErrorId : Windows System Error 52,New-NetNat

What Should Happen?

It was working perfectly on Feb 17. The VM booted, network connected, API was reachable, keepalive was running. Then on Feb 18, a version check happened (1.1.3541), and today (Feb 23) the app is suddenly classifying your system as "unsupported" and actively deleting your VM bundle files.
The culprit is the Claude Desktop auto-update from 1.1.3363 (which worked) to 1.1.3541 (which broke platform detection). You can see it — the service binary path points to 1.1.3541 but the VM bundle was downloaded under 1.1.3363. The new version's yukonSilver platform check is incorrectly failing on your system.
The NAT situation is actually fine — the HNS network exists with the correct 172.16.0.0/24 subnet and already has a NatName assigned (NAT9C38C466-7F33...). That's why the New-NetNat command threw the duplicate error.

Error Messages/Logs

see above

Steps to Reproduce

it is a fwd regression misfit

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

the Claude Desktop auto-update from 1.1.3363 (which worked)

Claude Code Version

1.1.3541 (which broke platform detection)

Platform

Other

Operating System

Windows

Terminal/Shell

VS Code integrated terminal

Additional Information

_No response_