Windows desktop 26.928.1915.0 hangs at startup logo; clean CODEX_HOME works once then hangs on relaunch #49721

App version

Microsoft Store package: OpenAI.Codex_26.928.1915.0_x64.
ChatGPT.exe version reported by Windows Reliability Monitor: 154.0.8037.57.
The About dialog is inaccessible during the hang.

Subscription

ChatGPT Plus.

Platform

Windows 11 Home, version 25H2, OS build 26200.9550, x64.

Issue

The desktop window opens but remains on the startup logo without reaching the main workspace. Investigated September 30, 2026.

A clean CODEX_HOME allowed one successful launch after approving the verified OpenAI Windows sandbox setup prompt. Onboarding completed, a Google Calendar task succeeded, and the main workspace loaded. After closing and reopening the app, the startup-logo hang returned. A new PowerShell window confirmed CODEX_HOME still pointed to the same clean folder.

Reproduction

1. Close the desktop app fully.
2. Launch normally.
3. The startup logo remains and the workspace does not load.

Clean-state test:

1. Back up existing Codex home.
2. Create an empty directory, set user-level CODEX_HOME to it, and sign out/reboot.
3. Launch, sign in, and approve codex-windows-sandbox-setup.exe (verified publisher OpenAI OpCo, LLC).
4. Complete onboarding and reach the main workspace.
5. Close and reopen the app.
6. Observe the startup-logo hang again.

Expected behavior

The desktop app should consistently reach the main workspace on reopening, preserving conversations and projects.

Troubleshooting completed

• Ended processes in Task Manager.
• Windows Repair and Reset.
• Uninstalled/reinstalled.
• Tested a phone hotspot.
• Launched with --disable-gpu (whether this build honors the flag is unverified).
• Renamed embedded browser profile, preserving the original.
• Temporarily disabled configured MCP servers; no resolution.
• A misplaced enabled=false under an MCP .env subsection caused a separate config validation error during testing. It was corrected, and the original pre-edit config.toml backup was subsequently restored. The original logo hang persisted.
• Tested clean CODEX_HOME as described above.

Diagnostics

Windows Reliability Monitor recorded MoAppHang / ChatGPT.exe stopped responding.
WER Report ID: a547637b-257d-4a78-b411-2dc14d353a7e.

Earlier logs showed successful account lookup, local executor rendezvous, cloud app-server initialization, and thread/list despite the unusable UI.

Failed relaunch with the clean-home environment setting produced:

2026-09-30T19:11:02.231Z error [electron-message-handler]
method=fs/readFile code=-32603
message="The system cannot find the path specified. (os error 3)"

2026-09-30T19:11:06.747Z error [electron-message-handler]
method=fs/readFile code=-32602
message="fs/readFile requires an environmentId"

2026-09-30T19:11:06.749Z warning [electron-message-handler]
routePattern=/tbo status=404 url=/tbo?limit=25

2026-09-30T19:11:17.091Z warning [electron-message-handler]
mcp_extension_tool_discovery_failed
error="MCP startup failed: timed out awaiting tools/list after 10s"
hostId=local pluginId=codex-app-tools@openai-bundled server=codex_app

2026-09-30T19:12:26.130Z error [electron-message-handler]
Conversation state not found

The same conversation identifier appeared in the original failed startup and the later failed relaunch with the clean CODEX_HOME setting. Identifier omitted publicly; available privately if needed. Persisted restoration state may merit investigation, but this does not establish causality or prove which state directory the app actually used.

An earlier bundled_plugin_status_unknown warning reported bundledVersion=26.928.20755, pluginName=chrome, marketplaceName=openai-bundled, reason=status_check_failed, and os error 3. Its installedPluginSourcePath was:

%USERPROFILE%\.codex\.tmp\bundled-marketplaces\openai-bundled\plugins\chrome

That directory existed and contained .codex-plugin, assets, docs, extension-host, node_modules, scripts, and skills. The specific missing internal file/dependency was not identified.

Original desktop log names:

• codex-desktop-5bf7d389-0ce8-4e8d-b3c2-6a87cd360a9c-55932-t0-i1-173424-0.log
• codex-desktop-5bf7d389-0ce8-4e8d-b3c2-6a87cd360a9c-55932-t1-i1-173425-0.log

Related reports and request

Potentially related symptoms: #49430, #48484, #43735. Identical root causes are not assumed.

OpenAI AI-assisted support directed me to file this issue. Please investigate startup readiness/restoration and provide a supported recovery procedure that preserves local history and projects. Raw logs, private project names, local username identifiers, account details, and conversation content are intentionally omitted from this public report.