What stops working after updates from Windows, Microsoft 365, Exchange, VMware, Veeam and other major vendors – with status, workaround and fix, continuously from the vendors’ official sources, complemented by reports from forums and the community and by targeted web research. Anything the vendor has not confirmed yet is labelled as a community report.
Sources last checked: 1 Nov 2026, 16:44
39 entries
A single user report describes the .NET cumulative update KB5127690 failing with error 0x80070bc9 on Windows Server 24H2 (build 26100.33650, Hyper-V VM). This is reported by users, not yet confirmed by the vendor. Microsoft has published no release-health entry for it; the error looks like a machine-specific servicing fault, not an update defect.
Microsoft · Windows Server 2024
One user reported that systems with Supermicro mainboards and Intel SATA RAID fail to boot after installing KB5122882. This is reported by users, not yet confirmed by the vendor; Microsoft has not documented the issue. The cause and the full scope are unknown.
Microsoft · Windows Server
Users report that File History copies files to the target drive, but the "Last copied on" date does not update and Previous Versions shows no entries. This is reported by users, not yet confirmed by the vendor. A related September 2026 File History bug was reportedly resolved by Microsoft, but no vendor source confirms the remaining problem.
Microsoft · Windows 11 File History
Let's Encrypt is shortening the validity of its certificates in stages, as required by the CA/Browser Forum Baseline Requirements. On 2027-02-10 the default classic profile moves to 64-day certificates. Users see the shorter validity at their next renewal after each date. Staging changes are deployed about one month earlier.
Let's Encrypt · TLS server certificates
Mozilla moved to a new GPG signing subkey for Firefox RPM packages, Linux tarballs and checksum files and revoked the previous key. On some RPM distributions the package manager cannot replace the key itself, so Firefox updates fail. Mozilla documents a manual workaround.
Mozilla · Firefox
Microsoft will disable Exchange Web Services (EWS) in Exchange Online in phases starting October 2026 and fully in April 2027. Free/Busy and MailTips from an Exchange Server organization to a different organization's Exchange Online tenant via an EWS-dependent Organization Relationship are affected. Microsoft is still evaluating a replacement path and has asked for feedback.
Microsoft · Exchange Online
After Microsoft Defender Antivirus update 4.18.26070.9 (released August 5, 2026), Windows and Windows Server may show notifications that Microsoft Defender Antivirus is turned off, although it works correctly. Microsoft resolved the issue in update 4.18.26080.4, released on September 17, 2026.
Microsoft · Windows 11, Version 26H1
Some USB Audio Class 1.0 devices might fail to start or produce no audio after installing Windows 11, version 26H2. Microsoft lists the same issue for other Windows client and server versions, where it originates from the September 8, 2026 security updates. For 26H2 the vendor status is Mitigated and a fix in a future Windows update is still being worked on.
Microsoft · Windows 11, Version 26H2
After installing Windows 11 version 26H2, Credential Guard protected machine accounts may lose their secure channel to an on-premises Active Directory domain. The cause is Machine Identity Isolation (MII), which Windows now honours; it is only supported with Windows Server 2025 domain controllers at Domain Functional Level 2025 or above. Microsoft has resolved the issue with updates released on 2026-09-22 and later.
Microsoft · Windows 11, Version 26H2
Microsoft plans to automatically migrate Windows Health Attestation compliance evaluation in Intune from the Device Health Attestation (DHA) service to Microsoft Azure Attestation (MAA) in the first half of 2027. It affects Windows 11 devices managed with Intune. Network, firewall, proxy and endpoint access must allow the new endpoints to avoid interruptions. No exact date has been announced.
Microsoft · Intune
Three time zone changes affect Windows devices in Alberta, British Columbia and Morocco. Morocco moved to UTC+0 on 2026-09-20; Alberta and most of British Columbia change permanently on 2026-11-01. Microsoft is releasing fixes across September and October 2026 and recommends temporary workarounds for devices that cannot be updated in time.
Microsoft · Windows
Exchange Web Services (EWS) changes in Exchange Online start between October 2026 and April 2027. Two on-premises scenarios are affected: hybrid setups with on-premises mailboxes that have online archives, and on-premises organizations with rich coexistence to a different Exchange Online organization. EWS is not deprecated on-premises.
Microsoft · Exchange Online
Microsoft plans to begin enforcing stricter logon requirements for the Exchange Online PowerShell module on 31 March 2027. Module versions older than 3.10.1 may fail to authenticate in certain interactive scenarios. Version 3.10.1 and newer continue to work normally.
Microsoft · ExchangeOnlineManagement PowerShell module
On 2027-02-10 Let's Encrypt moves all subscribers to certificates with a 64-day lifetime by default. Certificates issued or renewed on or after that date are affected; valid certificates are not revoked. Renewal jobs with hard-coded timings may fail to renew in time.
Let's Encrypt · TLS certificates (ACME)
Manitoba is permanently moving to UTC-5 and will not set its clocks back on November 1, 2026. Windows devices in Manitoba are affected because their time zone data does not yet reflect this. Microsoft states a fix is releasing in October 2026 and recommends a temporary workaround for devices that cannot be updated in time.
Microsoft · Windows time zone data
Certificates used to establish trusted connections to Windows Update expire on May 17, 2027 and June 19, 2027. Devices without the replacement certificates will lose access to Windows Update. Most up-to-date, supported devices need no action. Devices receiving updates from WSUS (Windows Server Update Services) are not affected.
Microsoft · Windows Update
RD Web Access in Windows Server relies on XSLT (Extensible Stylesheet Language Transformations), which is being disabled in Chromium-based browsers such as Microsoft Edge and Google Chrome. Once it is disabled, the RD Web Access page fails to render and users cannot reach it. Microsoft documents workarounds and asks admins to adopt one before the browser change reaches their users.
Microsoft · RD Web Access
After the Windows updates of September 22, 2026 (KB5124010) and later, some applications that need to decode AC-3 (Dolby Digital) audio might close unexpectedly. Microsoft has resolved the issue with the updates released October 13, 2026 (KB5127648) and later.
Microsoft · Windows 11, Version 26H2
After the September 2026 preview update, non-admin users might be unable to connect via Remote Desktop to devices that have Administrator protection enabled. Microsoft resolved the issue with updates released on 2026-10-28. For Windows 11 24H2 the release health page still shows the issue as mitigated, with a fix planned for a future update.
Microsoft · Windows 11, Version 26H2
After installing Windows 11, version 26H2 and subsequent updates, some devices may fail to load the desktop after sign-in. The issue was mainly observed on Azure Virtual Desktop (AVD) hosts using FSLogix, more often with some existing user profiles. Microsoft resolved it with the updates released on 2026-10-13 (KB5127648) and later.
Microsoft · Windows 11, Version 26H2
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