Windows 11 Insider Experimental (26H1) Preview Build 28120.3151

Release date: 2 October 2026

Changes and improvements gradually being rolled out*

This update includes a small set of general improvements and fixes that improve the overall experience for Insiders running this build on their PCs.

Magnifier now gives you more control over how you zoom. You can type an exact zoom percentage directly in the Magnifier toolbar to land on precisely the level you need.
We've also added preset step increments (5%, 10%, 25%, 50%, 100%, 150%, 200%, and 400%) to the Settings dropdown, so you can jump to common levels in a single click. Whether you need a subtle boost or a dramatic close-up, Magnifier adapts to how you want to zoom.

Enter an exact percentage or jump to preset steps - 5% up to 400%.

We're updating Cloud rebuild, the recovery option that restores a Windows 11 PC to a clean, known-good state by performing a full OS reinstall, with two additions.
Cloud rebuild can now sanitize the device's drives as part of the rebuild. When you start a rebuild in WinRE, choose Remove files if you're keeping the PC, or Remove & sanitize files before recycling, returning, or reassigning it. The sanitize option uses the storage hardware's erase capability to securely erase data before Windows is reinstalled and is irreversible.
IT administrators can now configure and start a Cloud rebuild remotely through the Recovery CSP, using either the currently installed build or a target build you specify.

UI showing new Cloud rebuild file removal options.

Customizations
- Improved File Explorer to keep folder view customizations, such as sorting and icon size preferences, consistent across different access paths and apps.
Address bar improvements
- The address bar now supports paths containing double backslashes and quotation marks, for example, C:\Users\user or "C:\Users\user", improving compatibility with a wider range of inputs.
- Improved reliability of the address bar suggestion dropdown so it now consistently closes after an item is selected.
Refinements to the rename experience
- Fixed an issue where text would be repeatedly selected while renaming items in folder views.
- Fixed an issue where updated names with case-only changes weren't immediately reflected in folder views across local and cloud storage.

These builds can be unstable and might be released with limited documentation.
Many features in the Experimental (26H1) channel are rolled out using Controlled Feature Rollout technology, starting with a subset of Insiders and ramping up over time as we monitor feedback to see how they land before pushing them out to everyone in this channel.
The desktop watermark shown at the lower right corner of the desktop is normal for Windows Insider pre-release builds.
Some features in active development we preview with Windows Insiders might not be fully localized, and localization will happen over time as features are finalized. As you see issues with localization in your language, report those issues to us via Feedback Hub.
Check out Flight Hub for a complete look at what build is in which Insider channel.