restart loops Archives

Winsage

May 10, 2026

Microsoft Confirms KB5083769 Breaks Macrium and Acronis Backups

Microsoft's April 2026 Windows security update, KB5083769, may disrupt image-mount operations for backup applications such as Macrium Reflect, Acronis Cyber Protect Cloud, UrBackup Server, and NinjaOne Backup due to the addition of the psmounterex.sys kernel driver to its Vulnerable Driver Blocklist. This action was taken to address a high-severity buffer overflow vulnerability, CVE-2023-43896. The inclusion of this driver in the blocklist has rendered several backup products inoperable, and Microsoft will not retract the block for security reasons. Administrators can use Event ID 3077 in the Code Integrity log to confirm that the blocklist is causing the failures. Microsoft advises updating backup applications to versions that include necessary driver protections instead of uninstalling or pausing the security patch. Additionally, the April updates have caused other issues, such as failures in Windows Server installations and devices booting into BitLocker recovery mode.

Winsage

May 5, 2026

April 2026 Windows Update Breaks Third-Party Backup Software by Blocking Vulnerable Driver

Microsoft will include the psmounterex.sys driver in its Vulnerable Driver Blocklist in the April 2026 security update, affecting third-party backup applications that use this driver for image mounting and Volume Shadow Copy Service (VSS) snapshots. This decision addresses CVE-2023-43896, a critical buffer overflow vulnerability. Affected software includes Macrium Reflect, Acronis Cyber Protect Cloud, UrBackup Server, and NinjaOne Backup on Windows 11, Windows 10, and Windows Server platforms. Users may face issues during image-mount operations, receiving error messages related to VSS timeouts and Code Integrity errors in the Event Viewer. To check if a system is affected, users can look for Event ID 3077 in the Code Integrity Operational log. Microsoft recommends upgrading to newer versions of backup applications that do not use blocked drivers and advises against uninstalling or delaying the April update. Additionally, the update may cause certain Windows Server 2025 devices to boot into BitLocker recovery mode and has led to out-of-band updates for Windows Server update failures and restart loops on domain controllers.

Winsage

May 4, 2026

Microsoft confirms April Windows updates cause backup failures

Microsoft has acknowledged that the April 2026 security updates have disrupted the functionality of various third-party backup applications using the psmounterex.sys driver, raising concerns among users. The issue primarily affects software leveraging the Volume Shadow Copy Service (VSS) snapshots, leading to failures due to VSS service timeouts. Notable impacted products include Macrium Reflect, Acronis Cyber Protect Cloud, UrBackup Server, and NinjaOne Backup, used on Windows 11, Windows Server, and Windows 10 devices. Disruptions can manifest as failures to mount backup image files, errors or timeouts when browsing or restoring from backup images, and error messages related to VSS timeouts. Microsoft updated its support documentation to clarify that the April updates included a security hardening change that added psmounterex.sys to the vulnerable driver blocklist to protect against a high-severity buffer overflow vulnerability (CVE-2023-43896). Affected users are advised to upgrade to newer application versions with updated drivers and not to uninstall or pause the security update. Users can check if the Microsoft Vulnerable Driver Blocklist is blocking a driver by looking for Event ID 3077 in the Code Integrity Operational log. Additionally, Microsoft has alerted users that some Windows Server 2025 devices may boot into BitLocker recovery mode after installing the KB5082063 update and has issued out-of-band updates to address installation failures and restart loops affecting Windows Server systems after the April 2026 updates.

Winsage

May 1, 2026

Microsoft fixes Remote Desktop warnings displaying incorrectly

Microsoft resolved an issue affecting the display of security warnings when opening Remote Desktop (.rdp) files across all supported Windows versions, including Windows 11, Windows 10, and Windows Server. This problem was particularly evident on devices with multiple monitors having different display scaling settings. The fix was included in the optional KB5083631 preview cumulative update for Windows 11. The issue arose after the installation of the April 2026 security update, which introduced security warnings to enhance protection against phishing attacks. Users reported misalignment and obscured buttons in the security dialog, making it difficult to interact with. Additionally, the April security updates caused issues with third-party backup applications on Windows 11 systems and led to restart loops and failures during update installations on Windows Server.

Winsage

May 1, 2026

April KB5083769 Windows 11 update causes backup software failures

The KB5083769 security update released in April 2026 has disrupted the functionality of various third-party backup applications on Windows 11 versions 24H2 and 25H2, primarily due to issues with the Volume Shadow Copy Service (VSS). Affected applications include Acronis Cyber Protect Cloud, Macrium Reflect, NinjaOne Backup, and UrBackup Server. Users have reported receiving an error message indicating that backups have failed due to VSS timeouts. Acronis has acknowledged the issue, stating it affects both Windows 11 Pro and Home editions, and warns of potential broader system issues. A temporary solution involves uninstalling the KB5083769 update or pausing Windows updates. Additionally, Microsoft has issued out-of-band updates for critical issues affecting Windows Server systems and warned that some Windows Server 2025 devices may encounter BitLocker recovery prompts after installing the KB5082063 update.

Winsage

February 17, 2026

Microsoft Windows 11 KB5077181 Update Triggers Infinite Restart Loop on Some Devices

Microsoft's Patch Tuesday update, KB5077181, released on February 10, 2026, has caused significant boot failures for users of Windows 11 versions 24H2 (OS build 26200.7840) and 25H2 (OS build 26100.7840), resulting in endless restart loops. Users are reporting over 15 reboot cycles, preventing access to their desktops. Issues include System Event Notification Service (SENS) errors and DHCP problems affecting internet connectivity. Installation errors with codes 0x800f0983 and 0x800f0991 indicate potential hardware, driver, or servicing stack incompatibilities. The update was intended to address 58 vulnerabilities, including six zero-days, but the boot loop issue has overshadowed these enhancements. CVE IDs and their CVSS scores related to the vulnerabilities addressed include: - CVE-2026-21510: 7.5 - CVE-2026-21519: 7.8 - CVE-2026-21533: 8.8 - CVE-2026-20841: 7.1 As of February 15, 2026, there is no "known issues" entry in Microsoft's release notes despite user reports. Users can uninstall the update through the Control Panel if their systems are accessible, or use the Windows Recovery Environment to execute commands for uninstallation if their systems are unbootable.

Winsage

February 16, 2026

Windows 11 KB5077181 Security Update Causing Some Devices to Restart in an Infinite Loop

Microsoft's security update KB5077181, released on February 10, 2026, for Windows 11 versions 24H2 and 25H2, has caused critical boot failures, leading to infinite restart loops for users. The update addresses 58 vulnerabilities, including six zero-day exploits, and introduces new Secure Boot certificates. Users have reported errors such as “a specified procedure could not be found” and DHCP failures, with installation errors like 0x800f0983 and 0x800f0991 affecting specific hardware. To resolve issues, users are advised to uninstall the update and pause Windows Update. Accessing the Windows Recovery Environment may also be necessary for persistent boot loops. While some users experienced improvements, the overall instability highlights risks associated with updates. Microsoft has not acknowledged any known issues related to this update as of February 15.

Winsage

April 18, 2025

Windows 11 24H2 Update Bug Triggers BSOD Error

Microsoft has acknowledged a significant bug in its Windows 11 24H2 updates, causing Blue Screen of Death (BSOD) crashes with the error code “SECUREKERNELERROR” (0x18B). This issue has escalated since the April 2025 Patch Tuesday update, affecting thousands of users globally. The bug leads to system crashes after installing the updates, resulting in persistent crash-restart loops or unbootable systems. Initially reported in March 2025, the problem gained traction following the April update, prompting Microsoft to confirm the bug and investigate its cause. Other issues include failures with Windows Hello and compatibility problems with games and software, particularly on ARM-based devices. To address the crisis, Microsoft has implemented a Known Issue Rollback (KIR) to disable the problematic code, which is being automatically pushed to affected devices, although users may experience a delay of up to 24 hours. Users are advised to keep their devices connected to the internet and restart their PCs multiple times to expedite the fix. For enterprise environments, IT administrators must manually deploy a specific Group Policy update. Microsoft is working on a permanent solution, expected in a future update, while also acknowledging related issues and committing to further fixes in the upcoming May 2025 update.

Winsage

October 1, 2024

Microsoft fixes Windows KB5043145 reboot loops, USB and Bluetooth issues

Microsoft has addressed issues caused by the Windows KB5043145 preview update, which led to reboot loops, system freezes, and failures in USB and Bluetooth device connectivity. Users reported their systems either loading the Automatic Repair tool or entering BitLocker recovery mode after repeated reboots. The update caused hardware connected via USB and Bluetooth, such as keyboards and printers, to malfunction, indicated by a yellow exclamation mark under the USB Host Controller in Device Manager. To resolve these issues, Microsoft implemented a Known Issue Rollback (KIR) to reverse the problematic update and is working on integrating this fix into an upcoming Windows update. Administrators managing affected Windows enterprise devices can resolve the issue by installing the Windows 11 22H2 KB5043145 240904_041021 KIR Group Policy, which requires a system restart to apply. Microsoft has previously addressed similar issues with updates affecting Windows Server 2019 and other versions.

Winsage

September 30, 2024

Windows 11 KB5043145 update causes reboot loops, blue screens

Microsoft has issued a cautionary note regarding the September 2024 KB5043145 preview update for Windows 11, indicating that users may experience reboot loops or freezes with blue screens. The update, released to address various issues, particularly with the Edge browser and task manager, has led to reports of devices restarting repeatedly or becoming unresponsive. Some users have noted that their devices automatically open the Automatic Repair tool after multiple restart attempts, and in some cases, BitLocker recovery is triggered. Microsoft is actively investigating these issues and encourages affected users to report their experiences through the Feedback Hub. The company is also working on fixes for other known issues related to boot problems and dual-boot systems with Secure Boot enabled, which arose from previous Windows security updates.