Build 26220.8474 is a Windows 11 Insider Preview build for the Beta Channel that is being delivered through Windows Update. Insider builds in Beta are typically rolled out gradually, so availability can vary by device and region. When a build is “live in Windows Update,” eligible devices enrolled in the Beta Channel will see it offered automatically under Settings → Update & Security → Windows Update as it reaches them during the rollout.
If a device is on an expiring or older Insider Preview build and does not see the new Beta build, checking for updates from Windows Update is required. If no updates appear and the device has previously switched channels or attempted to stop receiving Insider builds without a clean installation, additional steps such as reinstalling from an Insider ISO or moving to another channel might be needed to continue receiving builds.
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