Microsoft released Windows 11 Insider Experimental (26H1) Preview Build 28120.3151 on October 2, 2026. Its most consequential change expands Cloud rebuild, which can reinstall Windows even when the operating system will not boot, with data-removal choices and remote administration. This is an Experimental-channel preview, not a feature that has reached general Windows 11 users. Source
Choose based on whether the PC will be kept
Cloud rebuild now offers Remove files and Remove & sanitize files. Microsoft points to the first choice when the same person will keep the PC, and the second before recycling, returning or reassigning it. Sanitization uses the storage hardware’s erase capability before Windows is reinstalled and cannot be reversed. Someone who only needs to repair a PC should not choose it merely because the labels sound similar; important files should be backed up before any rebuild begins. Source
IT administrators can configure and start Cloud rebuild remotely through the Recovery CSP. They may reinstall the currently installed build or specify a target build. That can help with managed PCs being recovered or reassigned, but it is not the same workflow as an individual selecting a reset option in Settings. Organizations still need to confirm the target device, data-retention decision and approval path before issuing the remote action. Source
Magnifier and File Explorer also change
Magnifier now accepts an exact zoom percentage in its toolbar and offers preset steps of 5%, 10%, 25%, 50%, 100%, 150%, 200% and 400%. That removes the need to click through fixed increments repeatedly and can be useful for low-vision users or precise screen inspection. Source
File Explorer is intended to keep folder-view choices such as sorting and icon size more consistent across access paths and apps. Its address bar now accepts paths with double backslashes or surrounding quotation marks, and Microsoft fixed issues involving the suggestion dropdown and rename behavior. These changes can be staged, so two PCs on the same build may not receive every feature at the same time. Source
Check the preview limits before installing
Microsoft warns that Experimental (26H1) builds can be unstable and may arrive with limited documentation. Some features use Controlled Feature Rollout, starting with a subset of Insiders, and experiments may change, disappear or never reach a public Windows release. On a PC where stability matters, check the enrolled channel and backup state first, then evaluate the build on a test device or another recoverable setup rather than installing solely for the feature list. Source