authentication issues Archives

Winsage

January 19, 2026

The Last Windows Security Updates of January 2026 Are Here

Microsoft released its first set of security updates for the Windows operating system and various products in January 2026, addressing over 110 vulnerabilities. The updates are available for all supported versions of Windows, with Windows 10 receiving fixes only through the Extended Security Updates (ESU) program. Windows 11 versions 24H2 and 25H2 are the main consumer releases benefiting from these updates. Approximately 112–114 security updates were released, with around 8 rated as Critical. At least one zero-day vulnerability is actively exploited. The updates include security fixes for Windows, Office, Edge, Azure, and server components. Windows 11 versions 23H2, 24H2, and 25H2, as well as Windows Server 2023 and 2025, have known issues. Windows 11 version 24H2 and 25H2 received security fixes for multiple vulnerabilities, while version 23H2 continues to receive support through enterprise servicing channels. Windows 10 updates are limited to ESU-enrolled systems, with general support ending in October 2025. Windows Server 2016, 2019, 2022, 2023, and 2025 received January security updates, addressing important vulnerabilities without disclosing any critical ones. Microsoft also released updates for Office products and SharePoint Server components. Known issues after the January updates include credential prompt failures and authentication issues in Azure Virtual Desktop and Windows 365, particularly affecting the new Windows App. Workarounds involve using the classic Remote Desktop client or the web-based RDP client. Additionally, devices with Secure Launch enabled may experience shutdown and sleep mode failures. Microsoft has provided out-of-band fixes for certain affected systems as of January 18, 2026. Users can manually install updates through the Windows Update feature, and it is recommended to create a full system backup before proceeding with updates.

Winsage

January 19, 2026

Emergency Windows 11 Updates Fix Shutdown And Remote Desktop Failures

Microsoft released two emergency out-of-band updates, KB5077744 and KB5077797, to address critical issues with Windows 11 following the January 2026 security updates. Users experienced problems with system shutdowns, hibernation failures, and Remote Desktop authentication issues. The updates target Windows 11 version 23H2 with Secure Launch enabled and also affect Windows 11 version 25H2, Windows 10 22H2 ESU, and Windows Server 2025. The updates are being distributed automatically via Windows Update, but manual intervention may be needed for devices with paused updates or managed through enterprise policies. Microsoft recommends affected users install the updates promptly to restore normal functionality.

Winsage

January 19, 2026

The Last Windows Security Updates of January 2026 Are Here

Microsoft released its first security updates for 2026 on January Patch Tuesday, addressing over 110 vulnerabilities across Windows, Microsoft Office, Edge, Azure components, and other services. The updates are available for all supported versions of Windows, with Windows 10 receiving security fixes only through the Extended Security Updates (ESU) program. Windows 11 versions 24H2 and 25H2 are the primary consumer releases receiving updates. Key details include: - Approximately 112–114 security updates were released. - Around 8 vulnerabilities are rated Critical. - At least one zero-day vulnerability is actively exploited. - Windows 11 version 24H2 and 25H2 received security fixes for multiple vulnerabilities, including remote code execution and privilege escalation. - Windows 11 version 23H2 (Enterprise & Education) continues to receive cumulative security updates. - Windows 10 updates are limited to ESU-enrolled systems, with no feature updates available. - All supported Windows Server versions received updates, addressing important vulnerabilities. - Known issues include shutdown and sleep mode problems for devices with Secure Launch enabled in Windows 11 23H2. - Microsoft Office updates were also released, including for Excel and Word 2016, and SharePoint Server components. Workarounds for known issues have been provided, and users can manually install updates through Windows Update.

Winsage

October 22, 2025

Microsoft Confirms Recent Updates Cause Login Issues on Windows 11 24H2, 25H2, and Windows Server 2025

Microsoft has identified an authentication issue affecting users of Windows 11 versions 24H2 and 25H2, as well as Windows Server 2025, due to updates rolled out since late August 2025. These updates have caused failures in Kerberos and NTLM protocols on devices with identical Security Identifiers (SIDs), leading to widespread login disruptions in enterprise networks. Users have reported repeated credential prompts, error messages, and compromised network access, including issues with Remote Desktop Protocol (RDP) sessions and Failover Clustering operations. Event Viewer logs indicate machine ID mismatches and potential session discrepancies. The problem is particularly severe in virtual desktop infrastructure (VDI) environments where multiple machines share SIDs. Microsoft has emphasized the importance of using the Sysprep tool to ensure unique SIDs during cloning, as the recent updates now strictly verify SIDs during authentication. IT administrators can temporarily alleviate the authentication blocks with a specialized Group Policy, but a permanent solution involves rebuilding devices using approved cloning procedures. As of October 21, 2025, no broader patch has been released.

Winsage

October 22, 2025

Microsoft: Recent Windows updates cause login issues on some PCs

Microsoft has acknowledged a significant issue affecting Windows systems following updates released since August 29, 2025, which are causing authentication failures on devices with duplicate Security Identifiers (SIDs). SIDs are unique alphanumeric strings used by Windows to manage user and computer accounts. The updates enforce checks on SIDs, leading to authentication failures, particularly impacting Windows 11 24H2, Windows 11 25H2, and Windows Server 2025. Users may experience failed remote desktop connections, "Access denied" errors, and failed login attempts despite valid credentials, along with SECENO_CREDENTIALS errors in the Event Viewer. Duplicate SIDs often arise from cloning Windows installations without proper preparation using the Sysprep tool. Microsoft recommends rebuilding systems with duplicate SIDs using supported methods and offers a temporary workaround through a specific Group Policy.

Winsage

October 21, 2025

Microsoft issues fix for Windows 11 update that bricked mouse and keyboard controls in recovery environment – here’s what you need to know

Microsoft released an out-of-band update to fix a significant issue with its Windows 11 security update (KB5066835) that rendered essential USB devices non-functional in the Windows Recovery Environment (WinRE). This fix was distributed to all Windows 11 users six days after the initial update. The flaw affected versions 24H2 and 25H2 of Windows 11 and Windows Server 2025. Users are advised to avoid resetting their PCs or entering recovery mode until further notice. Additionally, the October update has other known issues, including problems with smartcard authentication, challenges in playing protected content with certain DVD and BluRay applications, failed updates using shared network folders, and potential loading failures for IIS websites. Microsoft has resolved the smartcard authentication issue but has not yet addressed the IIS website problem. In recent months, Microsoft has faced multiple bugs associated with its updates, including SSD malfunctions in August and a "latent code issue" in its Intune software in April. Last year, a bug led to unexpected upgrades for older Windows Server versions, causing system crashes, and Microsoft had to retract a preview of a Windows 11 update due to identified problems.

Winsage

October 20, 2025

Microsoft fixes Windows Server Active Directory sync issues

Microsoft is addressing an issue with Active Directory functionalities for certain Windows Server 2025 systems after the installation of the September 2025 security update (KB5065426). The problem affects applications using Active Directory directory synchronization (DirSync), particularly for large security groups exceeding 10,000 members, resulting in incomplete synchronization. To resolve this, IT administrators can implement the Known Issue Rollback (KIR) Group Policy on affected devices. For non-managed devices, a temporary fix involves adding a registry key at the specified path with a specific name, type, and value. Additionally, Microsoft is working on resolving a bug affecting Windows updates on Windows 11 24H2 and Windows Server 2025, as well as addressing smart card authentication issues and HTTP/2 localhost connection disruptions following recent security updates.

Winsage

June 16, 2025

Windows Server update may disrupt IP refreshes

Microsoft has acknowledged that the June security update has caused complications for users of Windows Server systems, specifically affecting the Dynamic Host Configuration Protocol (DHCP) service, which is failing and leading to improper functioning of IP refreshes. The issue impacts multiple versions of Windows Server, including 2016 (KB5061010), 2019 (KB5060531), 2022 (KB5060526), and 2025 (KB5060842). Users have reported that the DHCP service may stop responding after installing the update, with one administrator noting their 2016 server crashed shortly after the update was applied. Microsoft is working on a solution and advises affected users to uninstall the update to restore functionality. The company has a history of DHCP-related issues dating back over a decade and has faced other problems with Windows Server updates in the past year, including issues with keyboard and mouse inputs and authentication challenges.

Winsage

June 16, 2025

Microsoft: June Windows Server security updates cause DHCP issues

Microsoft has identified an issue with the June 2025 security updates that causes the Dynamic Host Configuration Protocol (DHCP) service to freeze on certain Windows Server systems. This affects the service's ability to apply renewals of unicast IP addresses, impacting network operations. Microsoft has acknowledged that the DHCP Server service may intermittently stop responding after the update and is working on a resolution. Additionally, other issues affecting Windows Server systems have been addressed, including application failures and authentication problems on domain controllers. Out-of-band updates were previously issued to fix bugs causing Hyper-V virtual machines to restart or freeze, and emergency updates were released for issues with Windows containers on certain Windows Server versions.

Winsage

June 12, 2025

Microsoft Resolves Windows Server 2025 Restart Bug Disrupting Active Directory Connectivity

Microsoft released updates in June 2025 to address critical issues affecting Windows Server 2025 domain controllers, specifically authentication failures and network connectivity problems. The updates, encapsulated in KB5060842, resolved issues stemming from security update KB5055523, which altered certificate validation methods for Kerberos authentication. This change led to logging errors for self-signed certificates and affected Windows Hello for Business Key Trust deployments. Additionally, a separate issue prevented domain controllers from managing network traffic correctly after restarts, causing them to revert to standard firewall profiles. Microsoft provided a temporary workaround for administrators to manually restart network adapters until a permanent fix was implemented. The June updates addressed a total of 66 vulnerabilities, including 10 rated as Critical, and recommended immediate installation. Microsoft advised against setting the AllowNtAuthPolicyBypass registry key to ‘2’ for domain controllers using self-signed certificates until the latest updates were applied.