[BUG] Cowork auto-repair deletes user session data then blocks its own retry - sessiondata.img preserved but sessiondata.vhdx required (Windows/MSIX); profile recreation silently deleted 22 local Cowork conversations

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 failures on Windows/MSIX. Related to #62937 (same error string, closed), #45076, #26452.

1. Cowork VM cannot start - preserve/require filename mismatch

cowork_vm_node.log:

[VM:start] Startup failed: Error: failed to set session disk path: session disk not found: ...\claudevm.bundle\sessiondata.vhdx
[VM:start] Auto-reinstalling workspace after startup failure
[deleteVMBundle] Deleted rootfs.vhdx
[deleteVMBundle] Reinstall files deleted (sessiondata.img and compressed cache preserved)

The cleanup preserves sessiondata.img; the runtime requires sessiondata.vhdx. A full-disk search of C: and D: finds neither file anywhere, so startup can never succeed.

2. The "repair" deletes an 8 GB user-data disk

deleteVMBundle deletes rootfs.vhdx to fix a missing-file error. It ran 2026-09-03 04:29 and again 2026-09-07 17:41.

3. It then blocks itself permanently

After the second attempt, every later start logs [VM:start] Skipping auto-reinstall (already attempted once) - reproduced continuously through 2026-09-10. The only fix is manually renaming .auto_reinstall_attempted inside the bundle. There is no UI affordance.

4. Profile recreation silently deleted local Cowork conversations

On 2026-09-05 an update sequence (1.40609 -> 1.44121 -> 1.46388.1/.2/.3/.4) recreated the Electron profile. main.log:

2026-09-05 11:51:52 [hybrid] boot: no hold { reason: 'no session' }
2026-09-05 11:54:02 [hybrid] boot: no hold { reason: 'no session' }
2026-09-05 11:57:59 [hybrid] boot: no hold { reason: 'no session' }

Corroborated by my own account's login_history.json from the Anthropic data export: three logins in six minutes, all browser_family Electron.

Two stores were emptied:

• claude-code-sessions\*.json (the desktop session index) - transcripts survived in ~\.claude\projects\, so 16 sessions were recoverable by rebuilding index entries. This matches #26452.
• - local-agent-mode-sessions\<account>\<org>\local_<uuid>\{.claude,outputs,uploads} - the local Cowork transcripts. Gone. Not in the Recycle Bin, absent from every live path, and no VSS snapshot predates the deletion.

A lot of Cowork conversations disappeared. 22 local Cowork sessions spanning 2026-03-28 to 2026-09-05 are still provable from C:\ProgramData\Claude\Logs\coworkd\user-<SID>.log, which survived the reset and records each session's name, local_<uuid> folder and mounted project path:

2026/07/05 18:44:53 [coworkd] mounting subpath for user inspiring-adoring-faraday (uid=1013, mode=rw): /mnt/.virtiofs-root/shared/d/<redacted> -> /sessions/inspiring-adoring-faraday

The sessions are enumerable. Their conversations are not recoverable.

Also worth flagging: the account data export (conversations, projects, memories, design_chats, light_metadata) contains no Cowork sessions at all - not even the cloud Cowork sessions visible in the web UI at claude.ai/cowork/<cse_id>. Users who export their data believing it is a backup are not backing up Cowork.

Environment: Claude Desktop 1.49585.0.0 (loss occurred under 1.46388.4), MSIX/Store install, Windows 11 Home 26200, Claude Code SDK 2.1.260. Profile redirected: %APPDATA%\Claude -> LocalCache reparse point -> D:\WpSystem\... (package data on a second volume).

Relation to #93247 (open, same 1.49585.0, filed the same day): that reporter restored claudevm.bundle intact from the Recycle Bin, mounted the VHDX under WSL2, and found 16 session folders but no conversation transcripts inside any of them. That is consistent with what I found here, and I think it answers their open question: the local Cowork transcripts do not live inside the VM at all. They live on the Windows side in local-agent-mode-sessions\<account>\<org>\local_<uuid>\.claude\. That is why restoring the bundle does not bring the sessions back, and why profile recreation destroys them.

What Should Happen?

1. The preserve step and the runtime should agree on the session-disk filename (sessiondata.img vs sessiondata.vhdx).
2. A missing session disk should be created, never trigger deletion of rootfs.vhdx. A repair path must not destroy an 8 GB user-data disk to fix a missing file.
3. .auto_reinstall_attempted should be clearable from the UI ("Reinstall workspace"), not a permanent dead end that requires renaming a hidden dotfile inside the bundle.
4. Profile migration must not delete claude-code-sessions\ or local-agent-mode-sessions\. If it must, it should back them up first and tell the user.
5. Local Cowork sessions should be recoverable - either synced like cloud Cowork, or stored outside the disposable VM/profile - and they should be included in the account data export.

Error Messages/Logs

cowork_vm_node.log:

2026-09-03 04:29:24 [info] [VM:start] Auto-reinstalling workspace after startup failure
2026-09-03 04:29:24 [info] [deleteVMBundle] Deleted rootfs.vhdx
2026-09-03 04:29:24 [info] [deleteVMBundle] Reinstall files deleted (sessiondata.img and compressed cache preserved)

2026-09-07 17:41:31 [error] [VM:start] Startup failed: Error: failed to set session disk path: session disk not found: C:\Users\<user>\AppData\Local\Packages\Claude_pzs8sxrjxfjjc\LocalCache\Roaming\Claude\vm_bundles\claudevm.bundle\sessiondata.vhdx
2026-09-07 17:41:31 [info] [VM:start] Auto-reinstalling workspace after startup failure
2026-09-07 17:41:31 [info] [deleteVMBundle] Deleted rootfs.vhdx

2026-09-08 21:01:00 [error] [VM:start] Startup failed: ... sessiondata.vhdx
2026-09-08 21:01:00 [info] [VM:start] Skipping auto-reinstall (already attempted once)
2026-09-10 16:14:22 [error] [VM:start] Startup failed: ... sessiondata.vhdx
2026-09-10 16:14:22 [info] [VM:start] Skipping auto-reinstall (already attempted once)

main.log (profile recreation + forced re-login):

2026-09-05 11:51:52 [info] [hybrid] boot: no hold { reason: 'no session' }
2026-09-05 11:54:02 [info] [hybrid] boot: no hold { reason: 'no session' }
2026-09-05 11:57:59 [info] [hybrid] boot: no hold { reason: 'no session' }
2026-09-05 11:51:52 [info] [MSIX] Filesystem virtualization active
2026-09-05 11:51:52 [warn] [privateFile] rename(...claude_desktop_config.json) failed (EXDEV), falling back to direct write

coworkd log (proves the sessions existed):

2026/07/05 18:44:53 [coworkd] mounting subpath for user inspiring-adoring-faraday (uid=1013, mode=rw): /mnt/.virtiofs-root/shared/d/<redacted> -> /sessions/inspiring-adoring-faraday

Steps to Reproduce

1. Windows 11, Claude Desktop installed from the Microsoft Store (MSIX). %APPDATA%\Claude is redirected via a LocalCache reparse point to a package folder on a second volume (D:).
2. Use Cowork local sessions over several weeks. Each creates local-agent-mode-sessions\<account>\<org>\local_<uuid>\{.claude,outputs,uploads}.
3. Let the desktop app auto-update through 1.40609 -> 1.44121 -> 1.46388.1/.2/.3/.4.
4. On the update that recreates the Electron profile, observe: Local Storage, IndexedDB, Cache, claude-code-sessions\ and local-agent-mode-sessions\local_*\ are all re-stamped/emptied, config.json reports a fresh first_launch_at, and the app forces re-login three times in six minutes.
5. Open Cowork. VM startup fails with "failed to set session disk path: session disk not found: ...\claudevm.bundle\sessiondata.vhdx".
6. Auto-repair runs: it deletes rootfs.vhdx, logs that sessiondata.img was preserved, but never creates sessiondata.vhdx.
7. Relaunch. Every subsequent start logs "Skipping auto-reinstall (already attempted once)". Cowork never starts again.
8. Search the whole machine: neither sessiondata.vhdx nor sessiondata.img exists on any volume.
9. Check the Cowork sidebar: all local sessions from before the update are gone. Their transcript folders under local-agent-mode-sessions are deleted, did not go to the Recycle Bin, and no VSS snapshot predates the deletion.

Workaround that restores Cowork (but not the lost sessions): rename .auto_reinstall_attempted inside claudevm.bundle, then fully quit and relaunch.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

1.44121.4 (Claude Desktop)

Claude Code Version

2.1.263 (Claude Code); Claude Desktop 1.49585.0.0

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_