[BUG] Cowork: legacy multi-folder projects disappeared from the account (desktop 2.2553.1) — conversations survive but are ungrouped

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?

On 2026-09-19 three Cowork projects disappeared from my account. Their conversations were not deleted: they survive and are now ungrouped ("no project"). The three that vanished are exactly the three that had two or more declared local folders. Every project with zero or one folder survived.

This looks like the pre-2026-09-06 multi-folder project type being dropped rather than migrated — see #92710.

Environment

• Claude desktop 2.2553.1, Windows 11
• Detected 2026-09-19 ~05:00 UTC-6
• Verified server-side, not only in the desktop UI: I loaded claude.ai in a clean browser session with the same account and the projects are absent there too.

What disappeared

| Project | Declared folders | Outcome |
|---|---|---|
| Breadbox | 2+ | gone |
| Dentvelop | 2+ | gone |
| Desarrollo del Entorno Cowork | 2+ | gone |
| Carbograf | 1 | survives |
| Personal | 1 | survives |
| 5 other projects (incl. one created 2026-03-31) | 0 | survive |

Age is not the discriminator: a project created 2026-03-31 with no folder survived, and the three that vanished were in daily use, the most recent one three days ago.

What I verified

1. Absent from all three tabs: Your projects, Organization, Shared with you.
2. There is no archived tab or archived section in this build, so this is not archiving.
3. In a conversation that belonged to one of them, the overflow menu offers "Add to project" — i.e. it now belongs to no project.
4. The "Add to project" picker lists only the seven surviving projects. Typing "bread" returns no match, only "+ Create bread". So they are not merely hidden from the projects page; they are not in the account's project picker.
5. Their conversations and content are intact; what is gone is the project container, its instructions, its knowledge and the grouping.

Why I think this is the multi-folder deprecation

#92710 reports that since 2026-09-06 new projects bind a single folder and are created as cloud projects, while pre-existing multi-folder projects kept working but stopped appearing in the iPhone app — already being treated as a deprecated type. Two weeks later, on the release that landed 2026-09-18, they stopped appearing anywhere in my account. Same direction, one step further.

This is different from #95496 and #94807, which are sidebar rendering regressions where the data is intact and visible on other devices. Mine is account state: a clean browser session on another surface shows the same absence.

Impact

These were production spaces with their own instructions and knowledge, used daily for company work. There was no announcement, no migration path, and no warning before deletion. The Help Center still documents the multi-folder workflow.

What Should Happen?

A project should not be removed from an account without an explicit action by the owner.

If the pre-2026-09-06 multi-folder project type is being deprecated, then before it stops being enumerated there should be: a public announcement, updated documentation, and a migration path that converts each legacy project into the new single-folder type while keeping its instructions, its knowledge and its conversation grouping.

Concretely, for this case:

1. Confirm whether these project records still exist server-side and can be restored.
2. If they can, restore Breadbox, Dentvelop and Desarrollo del Entorno Cowork with their conversations regrouped.
3. If the removal is intentional, say so publicly, so that other accounts still holding legacy multi-folder projects can convert them before losing them.

Error Messages/Logs

Steps to Reproduce

I cannot offer a deterministic repro, because the removal happened on its own between sessions. What I can give is the exact state before and after, and a check other users can run on their own accounts.

Before (working, for months):

1. In Claude desktop, before 2026-09-06, create a Cowork project and attach two or more local folders to it (the multi-folder projects described in the Help Center and in #92710).
2. Use it normally. The project appears under "Your projects" and its conversations are grouped under it.

After (2026-09-19, desktop 2.2553.1, Windows 11):

1. Open claude.ai/projects, in the desktop app or in a clean browser session with the same account.
2. Every project that had two or more declared folders is gone from "Your projects", "Organization" and "Shared with you".
3. Open any conversation that belonged to one of them: its overflow menu now offers "Add to project", i.e. it belongs to no project.
4. Open that "Add to project" picker and type the name of the vanished project: it is not listed, only "+ Create <name>" is offered.
5. Projects with zero or one declared folder are unaffected.

Check for other users: count how many declared folders each of your projects has. In my account the split was exact — 3 projects with 2+ folders gone, 7 projects with 0 or 1 folder intact.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

pre-2.2553.1 (projects were still present before the 2026-09-18 update)

Claude Code Version

Claude desktop app 2.2553.1 (Cowork) — not the Claude Code CLI

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

This is the Claude desktop app (Cowork), not the Claude Code CLI, so the "Claude Code Version" and "Terminal/Shell" fields above do not map cleanly; I filled them with the closest accurate values.

Related issues:

• #92710 — since 2026-09-06 new projects bind a single folder; legacy multi-folder projects kept working but stopped appearing in the iPhone app. This issue is the next step of the same behaviour: they stopped appearing anywhere.
• #76694 — "Choose a folder" removed from new projects after the Chat/Cowork merge, open since July with no response.
• #95496 and #94807 — sidebar sections disappearing after recent updates. Those are client-side; data stays visible on other devices. This one is not: a clean browser session on the same account shows the same absence.

I can provide the project names, approximate creation dates and the IDs of the orphaned conversations privately if that helps locate the records.