Windows desktop: downloading a generated TAR artifact fails with an error

What version of the Codex App are you using?

ChatGPT / Powered by Codex & OWL, version 26.1027.30824, released October 29, 2026, as shown in About.

What platform is your computer?

Windows 11, using the desktop app; the artifact was generated in a Codex cloud/sandbox workspace.

What issue are you seeing?

Attempting to download a generated TAR artifact from the workspace file view produces the red error message “Artefakt konnte nicht heruntergeladen werden” (artifact could not be downloaded). In the observed case the artifact was named kuma-api-checker-image.tar, intended to transfer a Docker image to the user's workstation. The user could not obtain the TAR through the app. A subsequent ZIP-based delivery was successfully downloaded and used.

The chat displayed a “Docker-Image herunterladen – 49 MB” link for the artifact. The workspace file view showed kuma-api-checker-image.tar, an “Öffnen” menu with “Speichern unter…”, and subsequently both “Datei konnte nicht geladen werden” and the red download error. The displayed 49 MB is an approximate UI value, not a verified byte count.

The exact failure cause is unknown: the error does not establish whether TAR is unsupported, whether file size or artifact transport caused the failure, or whether the TAR itself was valid. The screenshot shows the error in the workspace file view. The issue was reported during a Linux-container delivery workflow on a Windows host; a Linux desktop reproduction has not been established.

What steps can reproduce the bug?

1. Generate a TAR artifact in a Codex cloud/sandbox workspace (observed filename: kuma-api-checker-image.tar).
2. Open the artifact in the Codex desktop workspace/file view.
3. Attempt to download it.
4. Observe the red “Artefakt konnte nicht heruntergeladen werden” error.
5. Compare with a ZIP delivery of the relevant files, which succeeded in the same broader workflow. This does not prove the format alone causes the error.

What is the expected behavior?

The app should allow generated TAR archives to be downloaded intact, or explain the actual failure and any supported size or format limitations. TAR is a common Linux and Docker image-transfer format.

Additional information

Additional user-provided screenshots show the following desktop configuration and diagnostic state:

• Windows installed-apps list reports ChatGPT package version 26.1027.3384.0; About reports 26.1027.30824 as above. These are separate displayed versions.
• Workspace dependencies are enabled; current bundle version displayed is 26.1029.11837.
• The workspace dependency diagnostic displayed “Codex-Abhängigkeiten sehen in Ordnung aus” (Codex dependencies look OK). This does not diagnose the artifact download directly.
• Agent environment: Windows-native. Integrated terminal: PowerShell. Default file-opening target: VS Code.

The screenshots have not been uploaded to this issue; the above is a transcription of their visible details.

Reproduction frequency, exact TAR byte count, checksum, detailed application logs, and behavior on Linux clients are not confirmed. No credentials or private files are included in this report.