Windows: local runner cannot start, CreateProcessAsUserW failed: 5 #25436

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

26.527.31326

What subscription do you have?

pro

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x6

What issue are you seeing?

Bug: Codex Desktop on Windows cannot launch local runner: CreateProcessAsUserW failed: 5

Summary

Codex Desktop cannot execute any local workspace command on Windows. The workspace folder is readable from PowerShell outside Codex, but Codex tool execution fails before the command starts with:

windows sandbox: runner error: CreateProcessAsUserW failed: 5

Environment

• OS: Windows
• App: Codex Desktop
• Workspace path: D:\temp\temp\Codex
• Shell: PowerShell 7.6.2 installed via MSI
• Controlled Folder Access: Off
• Workspace sandbox mode shown in thread: workspace-write
• Writable root shown in thread: D:\temp\temp\Codex

Reproduction

1. Open Codex Desktop on Windows.
2. Open workspace: D:\temp\temp\Codex
3. Ask Codex to read/list the folder.
4. Codex attempts to run:

   Get-ChildItem -Force -LiteralPath 'D:\temp\temp\Codex'
   

What steps can reproduce the bug?

Environment

• OS: Windows
• App: Codex Desktop
• Workspace path: D:\temp\temp\Codex
• Shell: PowerShell 7.6.2 installed via MSI
• Controlled Folder Access: Off
• Workspace sandbox mode shown in thread: workspace-write
• Writable root shown in thread: D:\temp\temp\Codex

Reproduction

1. Open Codex Desktop on Windows.
2. Open workspace: D:\temp\temp\Codex
3. Ask Codex to read/list the folder.
4. Codex attempts to run:

   Get-ChildItem -Force -LiteralPath 'D:\temp\temp\Codex'
   

What is the expected behavior?

Codex should be able to launch its local helper/runner and read files inside the configured workspace.
Actual BehaviorCodex fails to spawn the local runner:
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execution error: Io(Custom { kind: Other, error: "windows sandbox: runner error: CreateProcessAsUserW failed: 5" })

The Node REPL helper also failed with a sandbox/process launch error:
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node_repl kernel exited unexpectedly
windows sandbox failed: spawn setup refresh

Additional information

Verification Outside CodexThe same folder is readable from an external PowerShell session:
powershell

Get-ChildItem -Force 'D:\temp\temp\Codex'

Output shows files successfully, including:
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PIMCO_PIMS_Income_Fund_A_TSR_AR.pdf
PIMCO_PIMS_Income_Fund_A_TSR_SAR.pdf
PIMCO_PIMS_Income_Fund_FSTM_AR.pdf
PIMCO_PIMS_Income_Fund_FSTM_SAR.pdf

Troubleshooting Already TriedConfirmed Controlled Folder Access is off.
Confirmed folder is readable outside Codex.
Tried explicit Codex file permission grant for D:\temp\temp\Codex.
Retried command after permission grant; same error.
PowerShell is MSI-installed, not Store-installed.
NotesThis appears to be a Codex Desktop Windows runner/session-token issue rather than a workspace ACL or shell issue, because both PowerShell command execution and Node helper startup fail before accessing files.