[BUG] Cowork tab missing in Claude Desktop despite healthy backend/service state

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?

cowork-tab-bug-report.md
Cowork tab is missing from Claude Desktop navigation despite CoworkVMService running, VM bundle present, plugin installed, and feature gate enabled — see attached bug report for full diagnostic details.

What Should Happen?

The Cowork tab should appear in the Claude Desktop sidebar navigation (alongside New, Projects, Artifacts, Scheduled, Dispatch, Customize), since the account is on the Pro plan and Cowork is included in that plan. All backend prerequisites are met — CoworkVMService is registered and Running, the VM bundle (claude-code-vm 2.1.217) is downloaded, the cowork-plugin-management plugin installed successfully, and the feature gate claudeai_cowork_backend_marketplaces is enabled (value=true) — so the tab should render without any additional setup.

Error Messages/Logs

No error messages appear anywhere in the UI. Relevant log excerpts:

main.log:
[info] [remoteUploadsMigration] upload_migration.gate_check gate=claudeai_cowork_backend_marketplaces value=true
[info] [WarmLifecycle:cowork] Initialized (arm=always)
[info] [WarmLifecycle:cowork] Destroyed
[info] [CustomPlugins] installPlugin: attempting remote API install for plugin plugin_0155zZVATbJU3jHUmPP9NvMC (source=unset, mode=cowork)
[info] [RemotePluginManager] Installed plugin: cowork-plugin-management

No occurrences of "yukonSilver" or "unsupported" found in main.log (searched explicitly), unlike other reported Cowork-tab-missing issues.

Get-Service -Name CoworkVMService | Format-List *:
Name                : CoworkVMService
Status              : Running
StartType           : Automatic
RequiredServices    : {staterepository}

Registry (HKLM\SYSTEM\CurrentControlSet\Services\CoworkVMService):
ImagePath: "C:\Program Files\WindowsApps\Claude_1.24012.1.0_x64__pzs8sxrjxfjjc\app\resources\cowork-svc.exe"

Note: an initial `sc query CoworkVMService` / `sc start CoworkVMService` returned no output at all in one terminal session (no status, no error) — inconsistent with the later Get-Service result showing Running. Not yet explained.

VM bundle present on disk:
C:\Users\gregn\AppData\Local\Packages\Claude_pzs8sxrjxfjjc\LocalCache\Roaming\Claude\claude-code-vm\2.1.217\claude (268,573,680 bytes, dated 2026-07-22)

Steps to Reproduce

1. Install Claude Desktop 1.24012.1.0 (0adcae), MSIX package, on Windows 11 Pro x64.
2. Sign in with a Pro plan account.
3. Launch the app and check the sidebar navigation.
4. Observe: only New, Projects, Artifacts, Scheduled, Dispatch, and Customize are shown — no Cowork tab.
5. Confirm Hyper-V is enabled (Windows Features).
6. Confirm CoworkVMService is installed and Running (Get-Service).
7. Confirm VM bundle is downloaded (claude-code-vm\2.1.217 present on disk).
8. Confirm cowork-plugin-management plugin installed successfully (per main.log).
9. Restart the app fully — Cowork tab still absent.
10. Press Ctrl+R to force reload — Cowork tab still absent.
11. Maximize the window (ruling out tab overflow at narrow width) — Cowork tab still absent.

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

1.24012.1.0 (0adcae)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_