# Codex extension fails to start: "The extension couldn't load its resources"

[YeNai-ShaoXianChao]

Description

The Codex panel fails to start after opening VSCode and shows:

Codex could not start. The extension couldn't load its resources.

Environment

• OS: Windows x64
• VSCode: 1.132.0 (commit df53daabb18cd157bdb08c7f01c34df936cf12f4)
• Extension: openai.chatgpt 26.803.41515 (win32-x64)
• Extension installed/updated: 2026-08-07

Steps to reproduce

1. Open VSCode.
2. Open the Codex sidebar or panel.
3. Wait about 30 seconds; the error "Codex couldn't load its resources." appears.

Console output (Developer Tools)

Key error lines:

index.html?id=...&extensionId=openai.chatgpt...
Loading the font 'data:font/woff2;base64,...' violates the following Content Security Policy directive: "font-src 'self' https://*.vscode-cdn.net". The action has been blocked.
...
Codex couldn't load its resources.

Troubleshooting already tried

• Developer: Reload Window
• Fully quit and restart VSCode
• Uninstall and reinstall the Codex extension
• Cleared %APPDATA%\Code\Service Worker\CacheStorage and ScriptCache
• Tried to roll back the extension version, but "Install Another Version..." failed with "Error while downloading VSIX: Canceled"

Additional analysis

From the extension source, initializeWebview sets a 30-second startup timeout for the webview and requires a ready message within that window. If VSCode's CSP blocks the data:font resource, the frontend may fail to initialize and trigger this error. Please confirm compatibility between 26.803.41515 and VSCode 1.132.0, and consider whether the webview's data:font should be served differently.

[YeNai-ShaoXianChao]

Regression in openai.chatgpt 26.803.41515: Codex panel fails to load resources

Summary

After updating to openai.chatgpt 26.803.41515, the Codex panel fails to start with:

Codex could not start. The extension couldn't load its resources.

Rolling back to openai.chatgpt 26.5730.61639 fixes the issue, so this appears to be a regression introduced in 26.803.41515.

Environment

• OS: Windows x64
• VSCode: 1.132.0 (commit df53daabb18cd157bdb08c7f01c34df936cf12f4)
• Broken version: openai.chatgpt 26.803.41515 (win32-x64)
• Working version: openai.chatgpt 26.5730.61639
• Extension update date: 2026-08-07

Steps to reproduce

1. Update Codex to version 26.803.41515.
2. Open VSCode and open the Codex sidebar or panel.
3. Wait about 30 seconds; the error "Codex couldn't load its resources." appears.

Console output (Developer Tools)

Key error lines:

index.html?id=...&extensionId=openai.chatgpt...
Loading the font 'data:font/woff2;base64,...' violates the following Content Security Policy directive: "font-src 'self' https://*.vscode-cdn.net". The action has been blocked.
...
Codex couldn't load its resources.

Troubleshooting already tried

• Developer: Reload Window
• Fully quit and restart VSCode
• Uninstall and reinstall the extension
• Cleared %APPDATA%\Code\Service Worker\CacheStorage and ScriptCache
• Rolled back to 26.5730.61639 by installing the VSIX directly: Codex works normally again

Additional analysis

From the extension source, initializeWebview sets a 30-second startup timeout for the webview and requires a ready message within that window. If VSCode's CSP blocks the data:font resource, the frontend may fail to initialize and trigger this error. Please confirm compatibility between 26.803.41515 and VSCode 1.132.0, and consider whether the webview's data:font should be served differently.

[STliuEN]

I can independently reproduce this issue on Windows.

Environment

• OS: Windows x64
• VS Code version: 1.132.0
• VS Code commit: df53daabb18cd157bdb08c7f01c34df936cf12f4
• Affected Codex extension: openai.chatgpt 26.803.41515

Behavior

The issue started immediately after the Codex extension was automatically updated on August 7, 2026.

Opening the Codex panel displays:

Codex could not start
The extension couldn't load its resources.

The webview requests React rendering but does not send the expected ready message within approximately 30 seconds. The Codex log then reports:

Webview did not finish starting

Diagnostics performed

I performed the following checks:

• Reproduced the issue using a completely clean and isolated VS Code profile.
• Compared the installed extension directory with the signed VSIX package.
• All 4,516 files were present, and the core resource hashes matched.
• Clearing the normal VS Code and extension state did not resolve the issue.
• Similar network-related errors are also present in an older working version, so those errors do not appear to be the direct cause.
• A data:font CSP warning is present. For diagnostic purposes, I tested with the CSP restriction bypassed locally, but the webview still timed out.

This does not appear to be caused by an incomplete or corrupted extension installation.

The CSP warning may be relevant, but bypassing it did not resolve the startup timeout, so I cannot confirm CSP as the root cause.

This appears to be a regression in the Windows webview initialization or compatibility behavior introduced in version 26.803.41515.

Workaround

Downgrading to an earlier Codex extension version restores normal operation.

Related report

Another user reported the same two-line startup error here:

#3801 (comment)

Screenshot

[williamIIliu]

I also get this issue on my linux cloud platform

[hugebenevolence]

Hi I found out that theres a solution for this one!

I have the same problem, and this solution have solved it. And this problem may be failed by authentication so we just remove the authen file btw ^^

• First, get into the .codex folder which has been placed in your user's folder, for example "C:\Users<your_account>.codex"
• Then, remove the "auth.json" file, and restart your ide and it solved!!

Hope that would help you guys!

[M-Kepler]

+1

[TheKrush]

I'm getting this as well and the previous comment about deleting the auth.json doesn't fix it

26.803.41515 release can help anyone affected get working again until the latest version is fixed.

[Jamie502]

Environment: Windows (VSCode) → Remote-SSH → Ubuntu 22.04
Broken: 26.803.41515 | Working: 26.727.40816

Logs:

text
[error] Request failed error={"code":-32603,"message":"No such file or directory (os error 2)"} method=fs/readFile
[error] [CodexWebviewProvider] Webview did not finish starting extensionVersion=26.803.41515 role=sidebar
Workaround: Downgrade to 26.727.40816 fixes it.

Same regression on Remote-SSH as Windows native. The fs/readFile error suggests local file init fails before network.After downgrading, the fs/readFile error still appears but does NOT block Codex startup anymore. The fatal issue is specifically the webview timeout in 26.803.41515. This error seems to be a separate non-fatal issue (possibly codex-core trying to read a missing plugin file). The real regression in 26.803.41515 is the webview initialization timeout.

[xy200303]

我发现解决办法是开启VPN代理就行，感觉是codex请求国外某些资源