[Windows] Codex extension fails with exit code 0xC0000135 (STATUS_DLL_NOT_FOUND) after Windows reinstall — missing VC++ Redistributable - A continous loading state

Environment

• OS: Windows 11 Pro
• VS Code: 1.109.4
• Extension: openai.chatgpt v0.5.75 ("Codex – OpenAI's coding agent")

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Problem

After a Windows reinstall, the Codex extension silently fails to start with no user-facing error.

The Codex sidebar shows a continuous loading indicator (infinite spinner) and never becomes usable. No error message, notification, or guidance is displayed.

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Root Cause

From the extension log at:

%AppData%\Roaming\Code\logs\<session>\window1\exthost\openai.chatgpt\Codex.log

LOG OUTPUT:

[error] [CodexMcpConnection] Codex app-server process exited unexpectedly
(code=3221225781 (0xc0000135), signal=null)
[error] [CodexWebviewProvider] Fatal error: Codex process is not available

Exit code 0xC0000135 corresponds to Windows error:

STATUS_DLL_NOT_FOUND

The bundled codex.exe depends on the following runtime DLLs:

• VCRUNTIME140.dll
• MSVCP140.dll
• VCRUNTIME140_1.dll

These are part of the Microsoft Visual C++ Redistributable 2015–2022, which is not included in a base Windows installation and gets removed after a system reinstall.

Because the dependency is missing, the Codex backend crashes immediately while the UI remains stuck showing an infinite spinner.

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Fix (for users)

Installing the Visual C++ Redistributable resolves the issue.

PowerShell command:

$url = 'https://aka.ms/vs/17/release/vc_redist.x64.exe'
$out = "$env:TEMP\vc_redist.x64.exe"
Invoke-WebRequest -Uri $url -OutFile $out -UseBasicParsing
Start-Process -FilePath $out -ArgumentList '/install', '/quiet', '/norestart' -Wait
````

After installation:

Reload VS Code
Ctrl + Shift + P → Developer: Reload Window