Win: After upgrading Codex, I'm getting "windows sandbox: runner error: CreateProcessAsUserW failed: 1920"

[Msirkovsky]

What version of Codex CLI is running?

0.128.0

What subscription do you have?

Plus

Which model were you using?

gpt-5.5

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What terminal emulator and version are you using (if applicable)?

Terminal

What issue are you seeing?

Codex can't read any file and shows this error:
Ran cmd /c dir
└ execution error: Io(Custom { kind: Other, error: "windows sandbox: runner error: CreateProcessAsUserW failed: 1920" })

• I’m blocked by the local execution environment before I can read or edit the repo. Every shell call fails at process launch with:

windows sandbox: runner error: CreateProcessAsUserW failed: 1920

That means I couldn’t open {redacted}, inspect the codebase, apply patches, or run tests. I also checked MCP resources and the GitHub connector fallback, but this local CodeReviewer workspace is not exposed there.

Once the shell runner is working again, I can continue from the plan file and implement it end to end.

What steps can reproduce the bug?

1. Start codex: "codex -a never -s workspace-write"
2. Ask to implement any plan

What is the expected behavior?

No response

Additional information

No response

[github-actions]

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

• Windows sandbox cannot spawn shell processes after escalation disabled #19189
• Windows: Sandbox cannot spawn any process (all commands fail with exit code -1073741502) #20346

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[daniel-gll]

Same issue "windows sandbox: runner error: CreateProcessAsUserW failed: 1920". Windows 10, Powershell 7.6.1

[wavman]

Same issue with Windows 11 25H2, PowerShell 7.6.1 and Codex Desktop 0.128.0.