Hi sagr gesrfse,
Microsoft does not publish public SHA256 hashes for LTSC IoT images on the standard download pages, which makes verification a bit tricky when the ISO is provided by a third-party store.
The hash is only available through Microsoft’s authorized channels, such as the Volume Licensing Service Center (VLSC) or the Microsoft OEM/IoT Partner Center. If your key is legitimate, your reseller should provide access to one of those portals, or at least provide a direct Microsoft download link, not a repackaged ISO.
If you want to check the integrity of the ISO you have, you can still compute its SHA256 hash using:
certutil -hashfile <filename>.iso SHA256
If your vendor cannot provide an official hash or access to a Microsoft download portal, that is a red flag, and you may want to clarify their licensing authorization.
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