[BUG] Cowork bash workspace: VM disk full — 36h+ outage (NOT Claude Code)

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?

Product: Claude Cowork desktop app (NOT Claude Code CLI)

The Cowork bash workspace has been completely broken for 36+ hours with the following errors:

Error Day 1:

no space left on device
failed to mount virtiofs-root
Session: confident-adoring-knuth

Error Day 2:

useradd exit 12 — cannot create directory /sessions/eager-elegant-lamport
Session: eager-elegant-lamport

Two different session names, same underlying error = host VM disk is full, not account-specific.

Account: josef.schasching@gmail.com
Support Conversation ID: 215474133856461
Duration: 36+ hours, persists across all new sessions and PC restarts
Impact: All automated Python jobs stopped (email processing, ecoDMS classification)

Email support only reaches bot (Fin) which cannot escalate this infrastructure issue.

What Should Happen?

The Cowork bash workspace should initialize successfully. Bash commands should execute without "no space left on device" errors.

Error Messages/Logs

OSError: [Errno 28] No space left on device
failed to mount virtiofs-root: exit status 1

Session names: confident-adoring-knuth, eager-elegant-lamport
Both sessions fail identically — this is a host VM infrastructure issue, not user-specific.

Steps to Reproduce

N/A — This is a Cowork desktop app infrastructure issue, not a Claude Code CLI issue.

The bash workspace fails immediately upon opening any new Cowork session.
No user action required to reproduce — the host VM disk is full on Anthropic's infrastructure side.

Account: josef.schasching@gmail.com
Affected sessions: confident-adoring-knuth, eager-elegant-lamport

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

N/A - this is a Cowork issue, not Claude Code

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

_No response_