Windows: Codex dependencies runtime 26.915.20218 fails to install due to SHA-256 checksum mismatch #46699

What version of the Codex App are you using?

Codex Desktop on Windows, Microsoft Store package OpenAI.Codex_26.915.4065.0_x64__2p2nqsd0c76g0.

The desktop logs report client version 26.915.31945 and bundled Codex Core/app-server version 0.155.0-alpha.9.2.

What platform is your computer?

Windows 11 x64.

What issue are you seeing?

Settings reports that Codex dependencies could not be installed/reinstalled.

The failure is not caused by a project dependency. Codex is trying to install its own primary runtime bundle:

codex-primary-runtime-win32-x64-26.915.20218.tar.gz

The download completes, but Codex rejects it during checksum verification.

Observed log event:

errorCategory=checksum_mismatch
failureStage=verify_checksum
bundleVersion=26.915.20218
target=win32-x64

The expected SHA-256 is:

06266088a7881b8fdc31adaf070e1db070ce4162e8c6137b212334b249d2e9c3

but the downloaded archive hashes to:

5911799885cacb45d0f95b1f1ed708cca2f5e5664d83291a95bf53643c18c368

The runtime URL in the log is:

https://persistent.oaistatic.com/codex-primary-runtime/alpha/26.915.20218/codex-primary-runtime-win32-x64-26.915.20218.tar.gz

The exact error is:

Checksum mismatch for 'https://persistent.oaistatic.com/codex-primary-runtime/alpha/26.915.20218/codex-primary-runtime-win32-x64-26.915.20218.tar.gz':
expected 06266088a7881b8fdc31adaf070e1db070ce4162e8c6137b212334b249d2e9c3,
got 5911799885cacb45d0f95b1f1ed708cca2f5e5664d83291a95bf53643c18c368.

This happened twice: once from the automatic startup installation (trigger=startup_missing) and again after manually choosing Repair/Reinstall (trigger=repair). Both attempts returned the same unexpected SHA-256.

What steps can reproduce the bug?

1. Run Codex Desktop on Windows x64.
2. Open Settings → Codex dependencies.
3. Attempt to install or reinstall the Codex dependencies.
4. The download runs for roughly a minute and fails.
5. Inspect the desktop log under the Codex MSIX LocalCache Logs directory.
6. The installer reports errorCategory=checksum_mismatch and failureStage=verify_checksum for runtime 26.915.20218.

What is the expected behavior?

The Windows primary runtime archive served by the CDN should match the SHA-256 digest in the runtime manifest so Codex can install the dependency bundle successfully.

Additional information

The previously installed primary runtime is still healthy:

bundleVersion=26.909.12148
installed=true
problemCount=0

Codex's own dependency diagnostics validate both bundled executables successfully:

Node:   v24.19.0 — passed
Python: 3.12.14 — passed
primary_runtime_validation_finished outcome=passed problemCount=0

Because two separate download attempts produced the same unexpected hash, this appears more consistent with an artifact/manifest publishing mismatch than a one-off corrupted local download.

No existing issue matching the exact 26.915.20218 Windows checksum mismatch was found before filing this report.