Computer Use fails on Windows 11 with CreateProcessAsUserW failed: 5

[Masssssssssssiiinnn]

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

26.609.4994.0

What subscription do you have?

ChatGPT Plus

What platform is your computer?

Windows 11 Home Single Language 25H2 (Build 26200.8655) x64

What issue are you seeing?

I am unable to use Computer Use at all.

My goal was very simple: I wanted Codex to perform basic desktop tasks for me, such as opening specific pages in Google Chrome before I arrive home, so that everything would already be prepared when I get back.

However, every attempt to use Computer Use fails before any visual interaction with Windows begins.

Examples of prompts that failed:

• Open Notepad.
• Open Calculator.
• Open Google Chrome.
• Open Netflix in Chrome.

The same error occurs every time:

CreateProcessAsUserW failed: 5

The failure happens before Codex can control the desktop, move the mouse, click anything, or interact with any application.

I also asked Codex to retry multiple times and reconnect to Windows, but the same error occurred repeatedly.

The helper reports:

windows sandbox failed: runner error: CreateProcessAsUserW failed: 5

What steps can reproduce the bug?

Feedback ID: 019ebe40-2480-7931-838c-e000e7aab3fc

1. Open the Codex App on Windows 11.

2. Start a new conversation.

3. Ask Computer Use to perform any desktop action.

Examples:

• Open Notepad.
• Open Calculator.
• Open Chrome.
• Open Netflix.

4. Codex attempts to connect to Windows.

5. The helper initialization fails.

6. The following error is returned:

CreateProcessAsUserW failed: 5

The issue is reproducible every time.

Additional troubleshooting performed:

• Restarted the computer.
• Reinstalled the Codex workspace.
• Ran workspace diagnostics successfully.
• Tested running Codex normally.
• Tested running Codex as Administrator.
• Checked Windows Defender history.
• Verified folder permissions.
• Verified helper executable existence.
• Executed helper manually.
• Collected logs.

The issue persists after all troubleshooting steps.

What is the expected behavior?

Computer Use should successfully connect to Windows and control the desktop.

For example, when I ask:

"Open Notepad"

Computer Use should launch Notepad and interact with Windows normally.

Likewise, when I ask it to open Chrome or a website, it should be able to perform those actions without failing during initialization.

I expected Computer Use to execute simple desktop automation tasks.

Additional information

I am not a programmer and I do not have a technical background in software development.

Because I did not know how to investigate the issue, I asked ChatGPT for help.

Together we performed a detailed troubleshooting process and collected logs from Codex.

The goal was simple: I wanted to use Computer Use for basic personal productivity tasks, such as opening specific pages in Chrome before I arrive home.

During the investigation we found:

• Workspace diagnostics completed successfully.
• Windows Defender showed no relevant blocks.
• Folder permissions appeared correct.
• The helper executable exists.
• The helper executable can be launched manually.

The helper executable launches successfully when executed directly.

It returns:

Error: runner: no pipe-in provided

This suggests that the executable itself is present and runnable, but Computer Use fails before establishing the expected communication channel.

The helper path is:

C:\Users\sofia.codex.sandbox-bin\codex-command-runner-0.140.0-alpha.2.exe

The operating system is:

Windows 11 Home Single Language 25H2
Build 26200.8655

The error appears consistently in logs as:

CreateProcessAsUserW failed: 5

I also collected logs and searched for CreateProcessAsUserW occurrences.

The error appears repeatedly in Codex session logs as:

windows sandbox failed: runner error: CreateProcessAsUserW failed: 5

No additional HRESULT, stack trace, Access Denied message, integrity level information, or token-related information was present in the logs.

Based on the investigation, the problem appears to occur during Computer Use helper initialization or Windows session creation, before any desktop interaction begins.

I can provide additional logs if needed.

[github-actions]

English translation:

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

26.609.4994.0

What subscription do you have?

ChatGPT Plus

What platform is your computer?

Windows 11 Home Single Language 25H2 (Build 26200.8655) x64

What issue are you seeing?

I am unable to use Computer Use at all.

My goal was very simple: I wanted Codex to perform basic desktop tasks for me, such as opening specific pages in Google Chrome before I arrive home, so that everything would already be prepared when I get back.

However, every attempt to use Computer Use fails before any visual interaction with Windows begins.

Examples of prompts that failed:

• Open Notepad.
• Open Calculator.
• Open Google Chrome.
• Open Netflix in Chrome.

The same error occurs every time:

CreateProcessAsUserW failed: 5

The failure happens before Codex can control the desktop, move the mouse, click anything, or interact with any application.

I also asked Codex to retry multiple times and reconnect to Windows, but the same error occurred repeatedly.

The helper reports:

windows sandbox failed: runner error: CreateProcessAsUserW failed: 5

What steps can reproduce the bug?

Feedback ID: 019ebe40-2480-7931-838c-e000e7aab3fc

1. Open the Codex App on Windows 11.

2. Start a new conversation.

3. Ask Computer Use to perform any desktop action.

Examples:

• Open Notepad.
• Open Calculator.
• Open Chrome.
• Open Netflix.

4. Codex attempts to connect to Windows.

5. The helper initialization fails.

6. The following error is returned:

CreateProcessAsUserW failed: 5

The issue is reproducible every time.

Additional troubleshooting performed:

• Restarted the computer.
• Reinstalled the Codex workspace.
• Ran workspace diagnostics successfully.
• Tested running Codex normally.
• Tested running Codex as Administrator.
• Checked Windows Defender history.
• Verified folder permissions.
• Verified helper executable existence.
• Executed helper manually.
• Collected logs.

The issue persists after all troubleshooting steps.

What is the expected behavior?

Computer Use should successfully connect to Windows and control the desktop.

For example, when I ask:

"Open Notepad"

Computer Use should launch Notepad and interact with Windows normally.

Likewise, when I ask it to open Chrome or a website, it should be able to perform those actions without failing during initialization.

I expected Computer Use to execute simple desktop automation tasks.

Additional information

I am not a programmer and I do not have a technical background in software development.

Because I did not know how to investigate the issue, I asked ChatGPT for help.

Together we performed a detailed troubleshooting process and collected logs from Codex.

The goal was simple: I wanted to use Computer Use for basic personal productivity tasks, such as opening specific pages in Chrome before I arrive home.

During the investigation we found:

• Workspace diagnostics completed successfully.
• Windows Defender showed no relevant blocks.
• Folder permissions appeared correct.
• The helper executable exists.
• The helper executable can be launched manually.
• Manual execution returns:

Error: runner: no pipe-in provided

• The helper path is:

C:\Users\sofia.codex.sandbox-bin\codex-command-runner-0.140.0-alpha.2.exe

• The operating system is:

Windows 11 Home Single Language 25H2
Build 26200.8655

• The error appears consistently in logs as:

CreateProcessAsUserW failed: 5

Based on the investigation, the problem appears to occur during Computer Use helper initialization or Windows session creation, before any desktop interaction begins.

I can provide additional logs if needed.

[github-actions]

Potential duplicates detected. Please review them and close your issue if it is a duplicate.

• Windows Codex app Chrome plugin fails with CreateProcessAsUserW failed: 5 #27792
• Node REPL kernel fails to start: CreateProcessAsUserW failed: 5 #27313
• Windows sandbox runner fails with CreateProcessAsUserW failed: 5 on Windows 11 #26803
• Windows sandbox: CreateProcessAsUserW failed: 5 - unfixable on Windows 11 Enterprise (Dell) #26896
• Access issue after the latest update #26644

Powered by Codex Action

[Cloud-Paladin]

Detailed investigation summary (Windows 11, Codex 26.609.3341.0, command-runner 0.140.0-alpha.2)

I hit the exact same CreateProcessAsUserW failed: 5 error. After a few hours of investigation, here's what I found:

Root causes identified

1. Base sandbox shell was broken by WindowsApps pwsh.exe alias
After installing PowerShell 7 MSI, Codex resolved pwsh.exe to C:\Users<u>\AppData\Local\Microsoft\WindowsApps\pwsh.exe (an App Execution Alias / reparse point) instead of C:\Program Files\PowerShell\7\pwsh.exe. CreateProcessAsUserW cannot resolve reparse points under the restricted sandbox token.

Fix: Delete the alias:
Remove-Item "C:\Users\85366\AppData\Local\Microsoft\WindowsApps\pwsh.exe" -Force
→ Shell commands now work on pwsh 7 MSI path.

2. PCManger ACL failure (Huawei/Microsoft PC Manager directory)
C:\Users<u>\PCManger (owned by BUILTIN\Administrators) consistently fails SetNamedSecurityInfoW during sandbox ACL setup, recorded as helper_unknown_error in setup_error.json.

Fix: Grant user Full Control on that directory.
→ Sandbox log now clean: setup refresh: processed N write roots (read roots delegated); errors=[]; read ACL run completed (no errors).

Still broken: Node REPL kernel

Even after both fixes:

• Kernel starts correctly (kernel_pid assigned, node.exe launched from cua_node runtime)
• But on any js execution request, the kernel's runner process creation fails with CreateProcessAsUserW failed: 5
• Diagnostics show: kernel_status: running, reason: stdout_eof, stderr: windows sandbox failed: runner error: CreateProcessAsUserW failed: 5

The shell command-runner works perfectly, but Node REPL's internal runner process creation fails under the sandbox token. This appears to be a separate code path from the shell sandbox.

Environment

• Windows 11 Build 26100
• Codex Desktop 26.609.3341.0
• command-runner 0.140.0-alpha.2
• PowerShell 7.6.2 MSI
• No MSIX/Store PowerShell 7
• WindowsApps pwsh.exe alias removed
• Sandbox user: CodexSandboxOnline

[IllusionVK]

Hi @Masssssssssssiiinnn, i had this same issue, and I asked codex to investigate this itself, and after changing config.toml

FROM
[windows]
sandbox = "elevated"

TO
[windows]
sandbox = "unelevated"

In-app browser was fixed for me. Maybe it works for you as well
(I am using Version 26.611.61753 • Released 17 June 2026)

[NovyXu]

I was able to get Computer Use working again on Windows after hitting what looked like two separate failure layers. Sharing the workaround in case it helps others.

Symptoms

Computer Use failed before any desktop interaction started. Basic prompts such as opening Notepad failed with:

windows sandbox failed: runner error: CreateProcessAsUserW failed: 5

Before that, I also saw a bundled runtime/package export error:

Package subpath './dist/project/cua/sky_js/src/targets/windows/internal/computer_use_client_base.js' is not defined by "exports" ... @oai/sky/package.json

What fixed it for me

1. Patch the bundled @oai/sky/package.json export issue

In the local bundled @oai/sky/package.json, add the missing export entry:

"exports": {
  ".": "./dist/project/cua/sky_js/src/index.js",
  "./dist/project/cua/sky_js/src/targets/windows/internal/computer_use_client_base.js": "./dist/project/cua/sky_js/src/targets/windows/internal/computer_use_client_base.js"
}

The local file was under a Codex runtime/plugin cache path similar to:

%LOCALAPPDATA%\OpenAI\Codex\runtimes\cua_node\<runtime-hash>\bin\node_modules\@oai\sky\package.json

or another bundled plugin cache location. I backed up the file before editing and verified the JSON remained valid afterward.

2. Set Windows sandbox mode to unelevated

In the Codex config file:

%USERPROFILE%\.codex\config.toml

I set:

[windows]
sandbox = "unelevated"

3. Fully quit and reopen Codex

After changing the config, I fully quit Codex and reopened it. Continuing in the same existing session did not appear sufficient.

4. Test with a minimal Computer Use task first

After restarting, I tested with a minimal task first:

@Computer open Notepad and type test

That worked. Only after that did I retry more complex desktop automation.

Notes

• Running Codex as Administrator did not appear to be the important fix in my case.
• The @oai/sky package export patch looks like a temporary workaround and may be overwritten by future Codex/runtime updates.
• The important durable config change for the CreateProcessAsUserW failed: 5 layer was switching Windows sandbox mode to unelevated and fully restarting Codex.
• This comment intentionally omits local usernames, exact machine paths, runtime hashes, and any personal workflow details.