Microsoft Store version of Codex (Stable & Beta) cannot be installed (0x803FB01A) on Windows 11 25H2 Insider

Open 💬 2 comments Opened Jul 1, 2026 by Skyrainy-M

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

Unable to install the app, so I cannot access the "About Codex" dialog. Microsoft Store Product ID: 9PLM9XGG6VKS

What subscription do you have?

ChatGPT Plus

What platform is your computer?

_No response_

What issue are you seeing?

Summary

The Microsoft Store version of Codex (both Stable and Beta) cannot be installed on my machine.

The installation reaches the "Downloading" stage and then fails with Microsoft Store error:

0x803FB01A

The Codex CLI works perfectly, and other Microsoft Store applications install normally.

---

Environment

Windows:

Windows 11 Pro
Version: 25H2
OS Build: 26200.8655

Microsoft Store:

Version: 22605.1401.13.0

Store Product:

Codex
Product ID:
9PLM9XGG6VKS
Publisher:
OpenAI

I also tested:

  • Codex Stable
  • Codex Beta

Both fail with exactly the same error.

---

Store Event Log

Microsoft-Windows-Store/Operational

Install state changing for product 9PLM9XGG6VKS:

Downloading => Error

Exception:
System.Runtime.InteropServices.COMException

Source:
InstallManager.cs

---

Winget

The Store package can be discovered normally.

winget install --id 9PLM9XGG6VKS --source msstore

returns

0x803FB01A

Verbose logs show:

  • Product metadata retrieved successfully
  • Entitlement acquired successfully
  • Market resolved successfully (HK)
  • Store package execution started
  • Download stage fails

---

Things already verified

The following all work correctly:

  • Microsoft Store
  • AppXSvc
  • ClipSVC
  • InstallService
  • Edge WebView2 Runtime
  • Windows Terminal
  • Microsoft PowerToys
  • Doubao (Store app)
  • Codex CLI (npm)

The Store itself works normally.

Only OpenAI Codex (Stable and Beta) cannot be installed.

---

Additional Notes

I initially suspected:

  • WebView2
  • VC++
  • Windows corruption
  • Microsoft Store corruption

After extensive troubleshooting, those appear unrelated because every other Store application installs successfully.

This issue appears specific to the Microsoft Store distribution of Codex.

Please let me know if there are additional logs I can provide.

The application has never been successfully installed, therefore I cannot provide the version from the "About Codex" dialog.

Both the Stable and Beta Microsoft Store versions fail to install with error 0x803FB01A before first launch.

What steps can reproduce the bug?

<img width="1008" height="783" alt="Image" src="https://github.com/user-attachments/assets/3421e247-c27a-4905-af96-c62359e689f2" />

<img width="1361" height="910" alt="Image" src="https://github.com/user-attachments/assets/db2686d1-59e7-4ba4-b858-49c221b65661" />

What is the expected behavior?

_No response_

Additional information

_No response_

View original on GitHub ↗

2 Comments

Skyrainy-M · 1 month ago

Additional investigation:

After several hours of troubleshooting, I believe this is not caused by Windows corruption.

Verified working:

  • Microsoft Store installs other applications normally (PowerToys, Windows Terminal, Doubao, etc.)
  • AppXSvc / ClipSVC / InstallService are all running normally.
  • Edge WebView2 Runtime is installed.
  • Codex CLI works correctly.
  • Microsoft Store itself works normally.

Only the OpenAI Codex Store packages fail:

  • Codex (Stable)
  • Codex (Beta)

Both fail with:

0x803FB01A

Store Event Viewer shows:

Downloading => Error

Store SDK:

System.Runtime.InteropServices.COMException

The failure happens after product metadata and entitlement are successfully acquired, when Microsoft Store starts downloading the package.

Windows:
Windows 11 Insider 25H2
Build 26200.8655

VirgilMing · 1 month ago

盲猜一个区域问题,往微软账户地区/系统账户这些方向排查,组合一下开关梯子