Windows 11’s Latest Security Update Disrupts Third-Party Backup Tools
Introduction
In late April, Microsoft rolled out the KB5083769 update for Windows 11, a mandatory security patch aimed at fortifying the operating system against a range of vulnerabilities. While the update delivered crucial fixes, it soon became notorious for causing a cascade of unexpected problems—ranging from BitLocker lockouts to disruptive boot loops. Now, weeks later, a new wave of issues has emerged: third-party backup applications are failing, leaving users without reliable data protection. This article explores the latest complications tied to KB5083769, the root cause, and what affected users can do in the interim.
The KB5083769 Update and Its Known Issues
Released on April 11, 2023, KB5083769 was part of Microsoft’s monthly Patch Tuesday cycle. It addressed over 100 security flaws, including zero-day exploits. However, soon after installation, reports surfaced of three major glitches:
BitLocker Lockouts and Boot Loops
Shortly after deployment, IT administrators and home users noticed that systems with BitLocker encryption began prompting for recovery keys unexpectedly. In some cases, the update triggered a boot loop—a repetitive restart cycle that prevented the device from loading Windows normally. For organizations relying on BitLocker for data security, this was a critical impediment.
Remote Desktop Bug
Another widely reported problem involved the Remote Desktop client. After applying KB5083769, many users experienced connection failures or sluggish performance when attempting to access remote machines. Microsoft eventually acknowledged the Remote Desktop issue but did not immediately provide a fix.
New Conflict with Backup Software
Just as the earlier issues began to settle, a more insidious problem came to light: the update is now conflicting with a broad range of third-party backup programs. These tools rely on Windows’ Volume Shadow Copy Service (VSS) to create consistent, point-in-time snapshots of system and user data. With the update, VSS interactions have become unreliable, causing backup jobs to fail or produce corrupted archives.
Affected Programs
User forums and tech news outlets, including BleepingComputer, have compiled a list of backup software known to be disrupted by KB5083769. Notable examples include:
- Acronis Cyber Protect Cloud – a popular enterprise-grade backup and cybersecurity solution.
- Macrium Reflect – widely used for disk imaging and disaster recovery.
- NinjaOne Backup – a remote monitoring and backup tool favored by IT teams.
- UrBackup – an open-source client/server backup system.
These applications either fail to initiate backups, crash mid-process, or restore incomplete data after the update is applied.
Root Cause: Volume Shadow Copy Service Bug
Investigations indicate that the culprit is a bug within the Volume Shadow Copy Service (VSS), a core Windows component that coordinates with backup apps to take snapshots without interrupting running processes. VSS is essential for creating “crash-consistent” or “application-consistent” backups, especially for databases and open files. After installing KB5083769, VSS may not properly finalize shadow copies, or it may report errors that cause backup software to abort operations prematurely.
Microsoft has not yet issued an official statement attributing the backup failures to a VSS flaw, but independent analyses strongly point to this service as the weak link. The VSS bug appears to be triggered under specific conditions—for example, when a backup job includes large volumes of data or when the system has high I/O activity.
Temporary Workaround and Pending Patch
Until Microsoft releases a cumulative update that resolves the VSS issue, affected users have a straightforward—but inconvenient—workaround: uninstall KB5083769. Doing so restores VSS functionality and allows backup programs to operate normally. However, this leaves the system exposed to the security vulnerabilities that the update was designed to fix.
Instructions for removal:
- Go to Settings > Windows Update > Update history.
- Click Uninstall updates.
- Select KB5083769 from the list and follow the prompts.
After removal, backups should resume without error. Yet this is a stopgap measure. Microsoft is expected to release a patch in the coming weeks, though no specific date has been announced. IT administrators are advised to monitor the Windows release health dashboard for updates.
Conclusion
The KB5083769 security update has proven to be a double-edged sword for Windows 11 users. While it patches critical vulnerabilities, it also introduces significant operational headaches—first with BitLocker and Remote Desktop, and now with backup software. The underlying VSS bug underscores the complexity of modern operating systems, where a single change can ripple through interdependent services. For now, the best course of action for those who rely on third-party backup tools is to remove the update and wait for an official fix. In the meantime, keep your systems protected by other means, and stay tuned for Microsoft’s next Patch Tuesday.