Request for Official SHA-256 Verification

Hello Lenco,

Thank you for posting your question on the Microsoft Windows Forum!

The most important finding is that the SHA-256 hash you calculated does not match the SHA-256 value published in Microsoft's verification document, despite the ISO having been downloaded directly from the official Microsoft Evaluation Center. [cdn-dynmed...rosoft.com], [microsoft.com]

Based on the information provided, it is not possible for community contributors on Microsoft Q&A to officially validate or certify a specific ISO hash value. Only Microsoft can authoritatively confirm whether a particular ISO currently being served by the Evaluation Center is the intended release.

What the available evidence suggests

The published verification document currently lists the following SHA-256 value for:

Windows 11 IoT Enterprise LTSC 2024 Evaluation x64
8ABF91C9CD408368DC73AAB3425D5E3C02DAE74900742072EB5C750FC637C195

However, the ISO filename you provided references build:

26100.1742.240906-0331

which suggests a refreshed image. A similar checksum mismatch has recently been reported by another user for the ARM64 evaluation ISO, where the build date of the downloaded image appeared newer than the date associated with the published verification document. In that discussion, it was noted that the most likely explanation is that the Evaluation Center image was refreshed while the linked checksum document had not yet been updated. [learn.microsoft.com]

What can be confirmed

If the ISO was downloaded from the official Microsoft Evaluation Center and the file was retrieved successfully without download errors, that supports authenticity, but it does not independently verify that the currently published checksum document corresponds to the exact ISO being served today.

Recommended next step

While awaiting official clarification from Microsoft, the following steps may help preserve evidence and determine whether the discrepancy is reproducible:

• Retain the downloaded ISO and verification results. Since the SHA-256 value does not match the published reference, I would avoid treating the media as officially verified until Microsoft confirms the discrepancy.
• Recalculate the file size and SHA-256 hash locally to ensure the recorded values are accurate.

$iso = "C:\Downloads\26100.1742.240906-0331.ge_release_svc_refresh_CLIENT_IOT_LTSC_EVAL_x64FRE_en-us.iso"
Get-Item $iso | Select-Object Name, Length, LastWriteTimeUtc
Get-FileHash -Path $iso -Algorithm SHA256

• Consider downloading the ISO again from the Evaluation Center using a newly generated download link. If a second download produces the same SHA-256 value, that would indicate the discrepancy is reproducible. However, a matching result across downloads still does not by itself provide official verification while the published checksum differs.
• Document the results and submit them through the appropriate Microsoft feedback channel.

It would be helpful to include:

Full filename
Architecture and language
File size in bytes
Calculated SHA-256
Published SHA-256
Download date

This information will help Microsoft determine whether the Evaluation Center media has been updated without a corresponding checksum update.

Microsoft References

• Windows 11 IoT Enterprise LTSC 2024 Evaluation Center [microsoft.com], [microsoft.com]
• Windows 11 IoT Enterprise LTSC 2024 Evaluation Hash Values [cdn-dynmed...rosoft.com]

One observation that may be relevant is that your reported mismatch closely resembles a recently reported case involving the ARM64 evaluation media, where the checksum document and the currently distributed ISO appeared to be out of sync. While that does not confirm the authenticity of your specific ISO, it does suggest that the discrepancy may be related to documentation lag rather than corruption.

I hope this information is helpful. If so, please click on Accept Answer and consider upvoting it. Doing so helps other community members identify useful solutions to similar issues.