[BUG] Cowork Windows: Multiple wvm- temp folders accumulate in AppData\Local\Temp and are never cleaned up

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?

Two related issues:

1. TEMP FOLDER ACCUMULATION: Each Cowork session creates a new wvm- temp folder in C:\Users\<user>\AppData\Local\Temp that is never deleted after the session ends. After multiple sessions, 4 folders accumulated totaling ~16.4 GiB:

• wvm-jtAa05 — 5.2 GiB
• wvm-BifIjw — 5.1 GiB
• wvm-ZRLOeH — 4.7 GiB
• wvm-R8U2ne — 1.4 GiB

1. VSS Shadow Copies: Each session also creates VSS shadow copies of ~8.6 GiB each that are not cleaned up, compounding the disk issue.

1. Cowork never successfully launched: Despite multiple attempts, Cowork never successfully connected or became usable. The VM appeared to start but sessions always failed. Cowork was enabled and the CoworkVMService was running, but the workspace never became functional.

Combined impact: C: drive (231 GiB SSD) dropped to 3.7% free space (8.6 GiB)

What Should Happen?

• Temp wvm- folders should be deleted automatically when a Cowork session ends
• VSS shadow copies created during sessions should be cleaned up automatically
• CoworkVMService should not run in the background when only using the Chat tab
• If Cowork fails to launch, temp files from the failed attempt should still be cleaned up

Error Messages/Logs

No error messages were displayed to the user. The space consumption was silent — folders accumulated without any warning or notification. Cowork sessions appeared to attempt startup but never completed successfully.

Steps to Reproduce

1. Install Claude Desktop on Windows 11 (latest version)
2. Enable Cowork tab
3. Attempt to use Cowork — session fails to launch successfully
4. Close Claude Desktop
5. Navigate to C:\Users\<user>\AppData\Local\Temp
6. Observe wvm- folder remaining, not deleted
7. Repeat steps 3-6 multiple times
8. Each failed session leaves a new ~4-5 GiB wvm- folder behind
9. Also run: vssadmin list shadows /for=C: to confirm shadow copies accumulating

Claude Model

None

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

Latest

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

System specs:

• CPU: Intel i7-9900k
• RAM: 16GB
• C: drive: 231 GiB SSD
• GPU: RTX 2070

Key findings:

• CoworkVMService runs in background even when only using Chat tab, not Cowork
• Disabling CoworkVMService in services.msc (Startup type: Disabled) stops accumulation and improves system performance
• Manual cleanup required: delete wvm- folders from Temp + run "vssadmin delete shadows /for=C: /all" + reboot
• Space was not released until after reboot

Possibly related issues:

• #25911 (wvm- temp path referenced, EXDEV rename failure)
• #22543 (VM bundle accumulation and performance degradation)
• #24918, #24945 (Cowork API unreachable on Windows)