Windows 11 26H1 Insider Builds: What’s New (Sep 1, 2026)
Quick Answer
26H1 Insider builds land, Bing and Store search toggles roll out, Exchange Online reports an auth outage, and Copilot gets August work updates.
- • New Insider builds: Microsoft shipped Beta Build 28020.2818 and Experimental Build 28120.2824 on August 31. The official announcement is intentionally brief; Pureinfotech’s same-day report identifies WinRE Wi-Fi profile reuse, personalization fixes, Magnifier icon refreshes, Emoji 17.0, and a temporary removal of the modern Print Management UI.
- • Search controls are opening globally: Settings is gaining staged toggles to turn off Bing web results and Store suggestions under Privacy & Security. The Next Web and Windows Latest report that the KB5120998 code is already installed and that activation is being enabled gradually.
- • M365 authentication outage: Exchange Online issue EX1464935 began at 17:30 UTC on August 31 and was linked to an authentication component. BleepingComputer reported impact across Exchange Online, Teams, SharePoint, OneDrive, Purview, and Defender XDR, with Microsoft testing a fix on part of its infrastructure at the time of the report.
- • KB5120998 known issue: Microsoft has confirmed that KB5120998 can change or revert mouse cursor personalization. BleepingComputer quotes Microsoft’s investigation notice, which also mentions reports of wallpaper changes.
- • Copilot gets work controls: Microsoft’s August Copilot roundup adds Cowork effort levels and /cost visibility, sharing links, Power BI data in Chat and Cowork, model-driven answer cards, Try again with another model, and deeper Notebook, Word, Excel, PowerPoint, Teams, and mobile workflows.
0126H1 Insider Builds Add Recovery and Visual Fixes
Microsoft’s Windows Insider Blog published new 26H1 builds on August 31: Beta Build 28020.2818 and Experimental Build 28120.2824. The official post is unusually short and confirms the build numbers without a long feature essay, so it is best treated as the source of record for what shipped and to which channel. For the feature inventory, Pureinfotech’s August 31 report supplies the practical detail and should be read as a secondhand but specific account of these builds.
The most consequential change for business devices is in Windows Recovery Environment. Pureinfotech says WinRE can now reuse a previously saved Wi-Fi profile, including certificate-based networks. That removes a common recovery headache: a device can reach the network during repair without someone manually re-entering credentials or importing a certificate in a stressful moment. If your fleet relies on 802.1X, this is worth adding to the Insider test checklist before the change reaches broader channels.
The personalization fixes are also user-visible. The report lists clearer wallpaper previews, DIB image support, better slideshow reliability, and a fix for wallpaper turning black after restart. Other changes include refreshed Magnifier toolbar icons, Emoji 17.0 characters, and a temporary removal of the modern Print Management UI that Microsoft plans to bring back in a later build. Insiders who depend on print administration should watch for that regression and keep the legacy path available during testing. For readers deciding whether Insider rings are appropriate, our Windows 11 Pro vs Home guide explains why Pro remains the practical choice for testing and policy management.
02Search Finally Gets Bing and Store Off Switches
Windows 11 is rolling out supported toggles that let users turn off Bing web results and Store suggestions in Search. The Next Web’s August 31 report describes the controls as a global change, two years ahead of the original DMA timetable in the EEA. They live under Privacy & Security rather than being buried in an advanced policy path, which makes the setting discoverable for ordinary users.
This is not just a cosmetic cleanup. Removing web and store content from local search can reduce latency, cut visual noise, and stop the Start menu from becoming an ad surface during a quick file or app lookup. For privacy-sensitive users, it also reduces the number of queries that leave the device for consumer search or store promotion. Windows Latest adds technical detail that the staged activation uses specific feature IDs, so even two machines on the same patch level can receive the setting at different times.
Administrators should treat the rollout as a configuration review trigger. The Digital Trends summary quoted in our collection says the feature is included in KB5120998 and activated gradually. That wording suggests the update already contains dormant capability. Before users discover it independently, decide whether enterprise policy should enforce a consistent Search experience, allow local choice, or disable web integration on compliance devices. If you are refreshing machines for the change, the Windows license buying guide is a useful baseline for choosing the right edition.
03Exchange Online Authentication Outage Hits M365
Microsoft tracked the Exchange Online incident as EX1464935, with auxiliary ID MO1465074, after it began at 17:30 UTC on August 31. BleepingComputer’s report identifies the failure as an authentication component problem and says it affected Exchange Online as well as Teams, SharePoint, OneDrive, Purview, and Defender XDR. That combination is what makes an authentication fault severe: users may see it as email failure even when the underlying problem reaches identity checks shared by multiple workloads.
The report also cites Downdetector peaks of about 5,733 Outlook reports and says Microsoft had isolated the authentication component and was testing a fix on part of its infrastructure at the time of publication. WindowsReport adds corroborating user reports across Microsoft 365 surfaces. We are not claiming resolution beyond that evidence; the verified status at the time of this article is that a fix was being tested, not confirmed fully deployed. For the latest state, check the Microsoft 365 admin center or service health dashboard rather than relying on social posts.
For IT teams, the actionable point is not to panic about Exchange itself but to rehearse the response pattern for shared identity failures. Communicate one incident ID, one status page, and one escalation channel. Avoid local password resets or token changes that do not address the root cause. Preserve logs and timestamps so you can distinguish authentication failures from client cache issues. If executives ask why Teams and file access are down when the alert says Exchange, the cross-service dependency is the answer.
04KB5120998 Cursor Problem Is Now Official
Microsoft has confirmed a known issue in Windows 11 KB5120998 that changes or reverts mouse cursor personalization settings. BleepingComputer quotes Microsoft’s notice directly and reports symptoms including a large white cursor on high-DPI displays and animated pointer settings reverting. The same notice mentions wallpaper-related reports. This upgrades the weekend user chatter from rumor to official known issue, so administrators can now cite Microsoft’s own acknowledgement.
The practical response is measured. Do not tell users to reinstall graphics drivers or recreate profiles until Microsoft identifies the component. Check Windows Update history, report affected devices through Feedback Hub as Microsoft requests, and keep screenshots of the before-and-after settings for support tickets. If your deployment ring policy blocks builds with known issues, this is exactly the case that process exists for. Otherwise, a temporary pointer reset is a cosmetic workaround, not a fix.
This also reinforces a simple update rule: security patches still matter, but preview and non-security updates deserve a canary period. Let the first ring absorb visual or personalization regressions, keep a rollback path defined, and document known issues before they reach every workstation. Our recent August 28 roundup covers the broader KB5120998 context if you need the deployment background.
05Copilot August Update Focuses on Work Control
Microsoft’s Copilot August 2026 roundup turns the assistant from a prompt box into a more measurable work system. The Tech Community post, published August 31, describes Cowork effort levels from Medium to Max, plus a /cost command that makes credit use visible. It also renames Scheduled to Automations, adds selected sentence or paragraph continuation in Chat, and introduces sharing links for a chat session or a single reply.
The data and productivity updates are broader. Power BI data can land in Chat and Cowork, model-driven answer cards cover weather, sports, finance, images, and video, and Try again lets users request another model. On mobile, an idea can move into an Outlook draft. Notebooks now have two forms: a lightweight Copilot app notebook and an OneNote workspace with cross-device sync, while Android multimodal capture is slated for September. Office gains are concrete too: Word hyperlink and image understanding with precise edit highlighting, Excel chat and change history, PowerPoint comment-to-task assignment with a brand strict mode, and Teams meeting-summary translation.
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The useful AI upgrade is not another demo; it is control over effort, cost, evidence, and handoff.
KeyStarter Editorial analysis of Microsoft’s Copilot August 2026 roundup
For IT, the governance questions are straightforward: which users may raise Cowork effort to Max, how credit consumption is reported, whether shared links can leave a tenant, and how Power BI permissions map into Chat. For individual users, start with effort levels, answer cards, and Notebook capture. Those features reduce copy-paste work without requiring a workflow redesign. A licensed Windows 11 Pro device and a stable productivity suite remain the practical foundation for these updates, especially when Copilot and Office files move across devices.
FAQ
Are the new 26H1 builds safe for my main PC?
Not for a production PC. Beta and Experimental Insider builds are for testing. Put them in a VM or spare device, back up first, and test recovery, print administration, display drivers, and line-of-business apps before rollout (Windows Insider Blog and Pureinfotech, Aug 31, 2026).
Can everyone turn off Bing results and Store suggestions in Windows Search now?
No. The controls are staged. The Next Web reports the settings are opening globally, while Windows Latest notes gradual feature activation. If the toggles are not visible, wait for activation or use supported enterprise policy where required.
Was the Microsoft 365 outage fixed?
The evidence collected for this article says Microsoft had identified an authentication component and was testing a fix on part of its infrastructure (BleepingComputer, Aug 31, 2026). Full resolution was not verified here; check the Microsoft 365 service health dashboard for the latest status.
What should I do about the KB5120998 cursor issue?
Treat it as an official known issue, avoid unsupported pointer repairs, submit Feedback Hub reports as Microsoft requests, and pause broad deployment if your policy blocks releases with unresolved known issues (BleepingComputer, Aug 31, 2026).
External References
- • Windows Insider Blog: Announcing new builds for 31 August 2026 (Aug 31, 2026)
- • Pureinfotech: Windows 11 26H1 builds 28120.2824 and 28020.2818 feature report (Aug 31, 2026)
- • The Next Web: Windows 11 Bing search toggles open globally (Aug 31, 2026)
- • Windows Latest: Windows 11 gets long-requested Search controls and feature IDs (Aug 28, 2026)
- • BleepingComputer: Exchange Online outage causes email failures and auth issues (Aug 31, 2026)
- • WindowsReport: Microsoft 365 outage affects Outlook, Teams, Store, and Azure users (Aug 31, 2026)
- • BleepingComputer: Microsoft says KB5120998 update resets mouse settings (Aug 31, 2026)
- • Microsoft Tech Community: What’s new in Microsoft Copilot – August 2026 (Aug 31, 2026)
This article was compiled with AI assistance for research and drafting and has been editorially reviewed. All sources are listed above.