[BUG] Windows: reinstall regenerates the `ant-did` device identity but preserves `remoteToolsDeviceName`, permanently orphaning existing Claude Code sessions ("Can't reach your computer")

Summary

Uninstalling and reinstalling Claude Desktop on Windows generates a new local device identity
(ant-did and the device registry keypair) while preserving the device name
(remoteToolsDeviceName).

The result is a silent, permanent break. Pre-existing Claude Code sessions still appear in the
sidebar and still carry the same device name, so the UI looks correct — but the identity they were
bound to no longer exists. Opening any of them shows:

Can't reach your computer It may be asleep or offline. This session will reconnect when it's back.

They never reconnect. There is no supported way to re-bind them, and no warning is given before
the reinstall that this will happen.

In my case 40 sessions across 7 projects (33.54 MB of transcripts) became permanently
unreachable this way.

Why this is confusing rather than merely broken

The device name survives the reinstall — it appears to be derived deterministically from the
machine. claude_desktop_config.json, written after the reinstall, contains:

"remoteToolsDeviceName": "desktop-<7-char-id>"

This is the same name the orphaned sessions carry — they are titled
desktop-<7-char-id>-<word>-<word> and still display it in the sidebar.

So by name, the sessions point at "this machine". Cryptographically, they point at an identity that
no longer exists. Nothing in the UI reveals the mismatch.

Evidence

Both identity files were created at reinstall time, hours after the affected sessions:

| File | CreationTime | Note |
|---|---|---|
| %APPDATA%\Claude\ant-did | 2026-08-21 16:54:49 | 48 bytes; only copy on the machine |
| %APPDATA%\Claude\ant-device-registry.json | 2026-08-21 16:58:22 | single entry {"<uuid>":"pk1:<...>"} |

The reinstall's Add deployment completed at 16:54:47 — two seconds before the new ant-did
appeared. The affected sessions were created between 02:14 and 10:25 the same day.

Additional checks:

• Every subfolder of %LOCALAPPDATA%\Packages\Claude_pzs8sxrjxfjjc\ was recreated at 16:54:47.

Only SystemAppData retains its original pre-reinstall timestamp.

• A recursive search of the user profile found no backup of ant-did or the device registry.

The previous identity is unrecoverable by any user-accessible means.

• No Claude/Anthropic entries exist in Windows Credential Manager.
• This account has never been signed in on any other device, so this is not a multi-device

attribution problem.

The error message is actively misleading

"It may be asleep or offline" attributes the failure to the user's machine. In my case the incident
genuinely did begin with a sleep/wake cycle, which made that reading entirely plausible — I spent a
long time investigating power and network faults before finding the real cause. The machine was
powered on, online, and running a healthy Claude install the whole time.

The promise that "this session will reconnect when it's back" can never be fulfilled, and the UI
gives no way to discover that.

Mitigating detail worth surfacing in the product

The conversation content is not lost. Transcripts remain intact at
%USERPROFILE%\.claude\projects\<project>\<session-id>.jsonl and can be resumed with:

claude --resume

run from the corresponding project directory. This creates a session bound to the new identity but
carrying the full prior history. Nothing in the product surfaces this, so from the UI the sessions
simply look dead.

Steps to reproduce

1. Create one or more Claude Code sessions in the Windows desktop app.
2. Uninstall Claude Desktop.
3. Reinstall it.
4. Open any pre-existing session → "Can't reach your computer", permanently.

Environment

| Item | Value |
|---|---|
| App version | 1.34493.1.0 |
| Package full name | Claude_1.34493.1.0_x64__pzs8sxrjxfjjc |
| Install type | MSIX, SignatureKind: Developer |
| Install source | https://claude.ai/download |
| Install method | Full uninstall, then clean install |
| OS | Windows 11 Pro 10.0.26200, x64 |
| Sessions affected | 40, across 7 projects |

Expected behaviour

1. ant-did and the device keypair should survive uninstall + reinstall under the same Windows user

profile — especially given the device name already does.

1. Failing that, offer an explicit re-bind path: *"This session was created on a previous

installation of this device — reconnect it here?"*

1. Distinguish "device offline" from "device identity no longer matches" in the banner. The current

text sends users to diagnose the wrong problem.

1. Warn before uninstall that existing Claude Code sessions will be permanently orphaned.
2. Point users to claude --resume when a session's device identity is gone but local transcripts

remain.

Related

• #88689 — the packaging defect that forced the reinstall in my case: Windows Repair and Reset are both permanently broken, leaving uninstall/reinstall as the only option
• #88068 — reports the Code tab "Older" list being wiped on reinstall (different symptom: the list

disappears; here the list survives but cannot connect). No device-identity mechanism identified.

• #88667 — "reinstall wipes claude-code-sessions"
• #76485 — Cowork device bridge no longer connecting to local folders

I have not seen the ant-did vs remoteToolsDeviceName mismatch described in any existing issue;
it appears to be the underlying mechanism behind several of the reports above.