Windows Codex Desktop: thread state corruption causes wrong prompts, queue timeouts, and scheduled-task heartbeat failures #39191

What version of the Codex App are you using (From “About Codex” dialog)?

ChatGPT Powered by Codex & OWL Version 26.814.41407 Released 17 de ago. de 2026

What subscription do you have?

ChatGPT Pro

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What issue are you seeing?

Codex Desktop on Windows has become extremely slow and intermittently unusable.

Existing threads frequently take a very long time to load or never finish loading. When a thread does load, the UI can show prompts or conversation content that belongs to another thread.

This makes thread isolation unreliable and creates a serious risk of continuing work in the wrong context.

Creating a new chat also frequently fails with one of these errors:

Error creating chat
App server request expired while queued
Error creating chat
Timeout

Scheduled tasks are also not running at their configured times. Attempting to start one can produce:

Could not start scheduled task

Heartbeat thread not found.

These symptoms are occurring together across multiple threads. They may indicate stale or corrupted mappings between thread IDs, renderer state, the app-server request queue, and scheduled-task heartbeat references. This is only a hypothesis, not a confirmed root cause.

The operational impact is severe:

Existing work cannot be accessed reliably.
Thread content cannot be trusted to belong to the selected thread.
New chats frequently cannot be created.
Scheduled tasks no longer execute reliably.
Normal Codex usage is repeatedly interrupted by timeouts.

What steps can reproduce the bug?

The issue is intermittent but currently happens frequently:

Open Codex Desktop on Windows.
Use or create multiple threads across normal work sessions.
Switch between existing threads from the thread list.
Observe that some threads remain loading indefinitely or take an unusually long time to open.
Open a thread and observe that the displayed prompts or content may belong to a different thread.
Try to create a new chat and submit a prompt.
Observe either App server request expired while queued or Timeout.
Wait for an existing scheduled task to run, or attempt to start it manually.
Observe that the task does not execute or fails with Heartbeat thread not found.

Observed repeatedly on August 18, 2026.

What is the expected behavior?

• Existing threads should load within a reasonable time.
• Each thread must display only its own prompts and conversation content.
• Creating a new chat should not expire while waiting in the app-server queue.
• Scheduled tasks should execute at their configured times.
• If a heartbeat thread reference becomes stale or missing, Codex should recover or recreate it automatically.
• A failure in one thread must not corrupt or contaminate the UI state of another thread.
• Temporary app-server failures should return a recoverable error without leaving the application in a permanently inconsistent state.

Additional information

Related reports were found, but none appears to cover this complete combination of symptoms:

#38832: Task/thread search and listing intermittently hang
#37401: Windows app-server queue saturation and request expiration
#23644: Stale conversation state causing timeouts
#35030: Scheduled runs hanging on thread operations
#12627: Prompt history shared between threads

This report differs because the same affected installation is experiencing thread-loading failures, cross-thread content appearing in the UI, new-chat queue timeouts, and missing heartbeat threads for scheduled tasks.

I can provide sanitized application logs, diagnostic feedback IDs, and timestamps privately if needed. Raw logs should not be posted publicly because they may contain prompt content, thread identifiers, local paths, and project information.