Claude Cowork Not Working on Windows: Fixes

When Claude Cowork is not working, work through five checks in order. Is Cowork where you are looking, now that it is merging into chat? Is your plan paid, and has your organisation turned it on? Is the desktop app current and open? On Windows, is the Virtual Machine Platform feature installed and the PC fully restarted? And is the problem one of Anthropic’s known issues? Most failures on Windows are the fourth one, and the error message usually says so.

This list is about Cowork itself. What the desktop app adds and how to install it is in the Claude desktop app; a local MCP server that will not connect is covered in Claude Desktop MCP not working.

Cowork is not showing up

First, check whether it has moved. Anthropic has announced that Cowork and chat are one Claude↗ (opens in a new tab), rolling out gradually from Pro and Max on web, desktop and mobile. Once you have the new experience there is no separate Cowork option to pick: you ask for what you need, and Claude decides whether that is a quick answer or a task. If your message box still shows separate Chat and Cowork options, you do not have it yet. Once you do, you cannot switch back, and your existing tasks, projects, connectors, skills and files carry over.

If there is neither a Cowork option nor the new experience, check the plan. Anthropic’s guide to getting started with Claude Cowork↗ (opens in a new tab) says Cowork is on paid plans only: Pro, Max, Team and Enterprise. On the desktop app it is on all paid plans; on the web and mobile, Enterprise has it only where an admin has enabled it. Then check you are signed in to the same Claude account on each device, because sessions sync through the account.

• Free plan: Cowork is not available. Upgrade, or ask your organisation for a seat.
• Team: Cowork is on by default, but an Owner can switch it off for the organisation.
• Enterprise: an Owner can switch it off organisation-wide or narrow it with groups and custom roles, so ask your admin before reinstalling anything.

Cowork will not start on Windows

Cowork sessions on the desktop that run on your own machine use a Linux virtual machine, isolated with Hyper-V on Windows. Anthropic’s page on deploying Claude Desktop for Windows↗ (opens in a new tab) says the app needs the Virtual Machine Platform feature for Cowork. If Cowork fails with “Missing HCS services: HNS, vmcompute, vfpext”, that feature’s services are not registered. Check it, turn it on from an administrator PowerShell, and restart:

# Is the feature on?
Get-WindowsOptionalFeature -Online -FeatureName VirtualMachinePlatform

# Turn it on, then restart the PC
Enable-WindowsOptionalFeature -Online -FeatureName VirtualMachinePlatform -All

• Restart, do not shut down. Anthropic notes that Fast Startup can leave the virtualisation services uninitialised after a shutdown and power-on, so use Restart from the Start menu.
• Installed per user? A per-user Add-AppxPackage install can finish without registering the Cowork virtualisation service. The documented fix is to redeploy machine-wide with Add-AppxProvisionedPackage. That needs an administrator, which is also why people without admin rights can install Claude but not use Cowork on the desktop.
• Running Windows inside a virtual machine or a VDI desktop? Anthropic says those are unsupported for Cowork unless nested virtualisation is available.
• Seeing “VM service not running”? Update the app. The Cowork changelog↗ (opens in a new tab) lists fixes for that error, and for sessions failing on some Windows installs, in recent versions.

It worked until a Windows update

One known issue matches this exactly. A Windows update released on 8 September 2026 left Cowork on Windows unable to run local commands, because its workspace could no longer reach the drive. Anthropic’s status page and changelog record it as resolved on 14 September, when Microsoft released a fixing update. Cloud sessions were not affected. If a local session still fails the same way, install the latest Windows updates and restart; reinstalling Claude does not help with this one.

The general lesson holds for the next one too. Before you reinstall anything, check status.claude.com and the Cowork changelog for a matching entry. A known issue with a date on it saves an afternoon.

It runs, but cannot reach files, the browser or other apps

Cowork sessions run in Anthropic’s cloud by default and keep going when you close your laptop. Anything on your own computer is reached through the desktop app, so these fail when it is closed or disconnected:

• Local files. Cowork only reaches folders you have connected in the desktop app, with the permissions you set there. If a file “does not exist”, check the folder is connected, not just open in File Explorer.
• Browser use. The built-in browser needs the desktop app open, and on Team and Enterprise an Owner can switch it off.
• Computer use, where Claude operates other apps. It is on Pro and Max only; Team and Enterprise do not have it yet. It must be switched on in the desktop app under Settings, General, and it asks before each app.
• Plugins with local MCP servers, which only run on the desktop. A local server that fails to connect is the job of Claude Desktop MCP not working.

Something is missing on Team or Enterprise

On an organisation plan, a missing feature is often a setting, not a fault. Anthropic’s page on Cowork on Team and Enterprise plans↗ (opens in a new tab) lists the switches under Organization settings, Cowork:

• Enable for your organisation: the master switch.
• Run Cowork in the cloud: on by default for Team, off at launch for Enterprise, where an Owner must turn it on and grant it to groups.
• The built-in browser: an Owner can turn it off.
• Allow “Automatically approve” mode: when off, that mode is missing from your selector.
• Allow “Always allow” for connector tools: off by default, so write tools ask every time.

Changes to these apply to new conversations only. If your admin has just switched something on, start a new task rather than retrying the old one.

How to report a bug to Anthropic

If none of this fixes it, report it. Anthropic’s page on how to get support↗ (opens in a new tab) describes the route on paid plans: in claude.ai or the desktop app, click your name in the lower left, choose Get help, and use Send us a message to reach the support team if the assistant cannot help. Replies come to the messenger and your account email. Reply to the same conversation rather than opening a second one.

1. Say what you did and what happened, in one or two sentences.
2. Paste the exact error text, such as “Missing HCS services”, and add a screenshot.
3. Give your Windows version, the Claude app version, and whether it was a cloud or a local session.
4. Say when it started, and whether a Windows or app update came just before.
5. List what you already tried from this page, so the reply does not start there.

For a single bad result rather than a broken app, the in-app feedback button is quicker. Anthropic’s Cowork safety guidance also asks for suspicious behaviour, such as a task acting on instructions it found in a file or web page, to be reported.

Keep the fault somewhere the team can see

A Cowork failure on one laptop tends to be a failure on every laptop with the same build, and the fix is usually an admin change: a Windows feature, a machine-wide install, a setting. Log it once where the team looks. On a fenbs board it is a bug task with a priority from 1 to 10, where 1 is the most urgent, a note with the error text and the machine, a plan with the steps, and a test status once someone has checked the fix. Claude can add the task itself over MCP, and History records who filed it and who moved it to Completed. fenbs has no assignee field or due dates, so put the owner and the date in the plan.