Shadow Copy Archives

Winsage

May 6, 2026

“Minimize downtime and simplify troubleshooting”: Microsoft’s powerful new recovery tool is quietly fixing System Restore. Here’s how it actually works.

System Restore is a recovery tool in Windows that allows users to revert their systems to a previous state, originating with Windows ME. It generates restore points that can be created manually or automatically, with a maximum retention of 60 days starting from the Windows 11 24H2 update in 2025. System Restore captures essential system files and settings but does not recover personal files. The new Point-in-Time Restore feature, introduced in 2025 and appearing in the Windows 11 Insider Experimental preview in April 2026, captures a broader range of data, including user files and applications, and operates on a scheduled basis with snapshots retained for up to 72 hours. It is optional for standard users, enabled by default for PCs with 200GB or more storage, and has storage limits set to 2% of total drive capacity. In enterprise settings, it is always enabled for Windows 365 Enterprise, maintaining restore points for up to one month and utilizing cloud storage. Point-in-Time Restore aims to improve the recovery experience and address limitations of the classic System Restore.

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

Windows 11’s April update is now breaking third-party backup apps

Microsoft rolled out update KB5083769 for Windows 11 to enhance security, but users have reported issues such as BitLocker lockouts, boot loops, and problems with Remote Desktop functionality. The update is causing compatibility problems with third-party backup applications, including Acronis Cyber Protect Cloud, Macrium Reflect, NinjaOne Backup, and UrBackup Server, due to a bug in the Volume Shadow Copy Service (VSS). Users experiencing backup failures are advised to uninstall update KB5083769 as a temporary solution until Microsoft releases a patch. The timeline for resolving these issues is currently unclear.

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

April 18, 2026

RedSun: Windows 0day when Defender becomes the attacker

A vulnerability has been discovered in Windows Defender that allows standard users to exploit a logic error in the file remediation process, enabling code execution with elevated privileges without administrative access. This flaw, identified by security researcher Chaotic Eclipse, occurs because Windows Defender does not verify if the restoration location of flagged files has been altered through a junction point. The exploit, named RedSun, takes advantage of a missing validation in the MpSvc.dll file, allowing attackers to redirect file restoration to the C:WindowsSystem32 directory. RedSun operates by chaining together four legitimate Windows features: Opportunistic Locks (OPLOCKs), Cloud Files API, Volume Shadow Copy Service (VSS), and Junction Points. The execution of the exploit involves monitoring shadow copies, triggering Defender's detection, synchronizing OPLOCKs, and ultimately writing malicious binaries to the System32 directory. The root cause is the lack of reparse point validation in the restoration process, and currently, no patch or CVE has been assigned for this vulnerability. It affects Windows 10, Windows 11, and Windows Server 2019 and later, and organizations are advised to implement behavioral detection strategies until a fix is available.

Winsage

April 9, 2026

BlueHammer: Windows zero-day exploit leaked

A proof-of-concept (PoC) exploit called BlueHammer has been released on GitHub, targeting an unpatched local privilege escalation vulnerability in Windows. The exploit, attributed to users Chaotic Eclipse and Nightmare Eclipse, has been modified by security researchers to work on updated versions of Windows 10, 11, and Windows Server. The exploit manipulates Microsoft Defender to create a Volume Shadow Copy, allowing access to sensitive registry files and enabling the extraction of NTLM password hashes. This facilitates the alteration of a local Administrator's password and subsequent login. The exploit can duplicate the Administrator's security token and create a malicious Windows Service that runs with SYSTEM privileges. While there are no reports of BlueHammer being exploited by malicious actors, researchers warn that such PoC code can be weaponized quickly. Microsoft has committed to investigating reported security issues related to this vulnerability.

Winsage

December 29, 2025

Windows 11’s Point-in-Time Restore: A Quiet Safety Net for When Things Go Wrong

Windows 11 Point-in-Time Restore is a recovery feature that captures snapshots of the system's state, including system files, applications, settings, and user data, allowing users to revert to a recent stable state when issues arise. It operates automatically once activated, using Volume Shadow Copy technology for comprehensive backups. The feature can quickly reverse changes made within the last 72 hours, addressing problems like faulty driver installations without requiring a complete reinstallation of Windows. However, it has limitations, such as storing restore points locally for a maximum of 72 hours, not recovering long-deleted files, and requiring significant storage space. To enable it, users must use ViveTool to unlock the feature, configure settings for snapshot frequency and retention, and access restore options through the Windows Recovery Environment if needed. It is particularly useful for casual users who frequently modify their systems but may not suffice for power users needing comprehensive backup solutions.

Winsage

November 27, 2025

See all the Windows 11 features that Microsoft has been testing so far in November — before the next big update

Microsoft has begun rolling out new features for Windows 11, including previews for versions 25H2 and 26H1, specifically build 28000.1199. Key updates include: 1. Xbox Full Screen Experience (FSE): This feature is being tested for all PCs with build 26220.7271, transforming the desktop into a console-like interface and reducing memory consumption by approximately 2GB. Users can activate it via Settings > Gaming > Full screen experience, and it requires enrollment in the Xbox Insider program. 2. Point-in-time Restore: This feature allows users to revert their computer to a previous state, recovering from issues like buggy updates or malware. It uses the Volume Shadow Copy Service to create restore points and is enabled by default on devices with a minimum of 200GB storage running Home and Pro editions. Users can manage it via Settings > Recovery > Point-in-time. 3. Voice Typing with Fluid Dictation: The Fluid Dictation feature is now integrated into Voice Typing, automatically correcting grammar and punctuation. It is enabled by default on Copilot+ PCs. 4. Microsoft Store App Uninstall Option: An "Uninstall" option for apps is now available in the Microsoft Store through the app's context menu on the "Library" page.