When Microsoft released the KB5083769 cumulative update for Windows 11 in April 2024, it was intended to patch critical security vulnerabilities and improve system stability. However, this seemingly benign security rollup has spiraled into a cascade of headaches for users and IT administrators alike. Initially, reports surfaced of BitLocker lockouts, boot loops, and a Remote Desktop glitch. Now, weeks later, a far more insidious issue has emerged: the update is systematically disabling and crashing popular third-party backup applications. This article unpacks the 10 most important things you need to know about this developing saga, from the root cause involving the Volume Shadow Copy Service (VSS) to practical steps you can take today.
1. The Update at the Center of the Storm: KB5083769
KB5083769 was released on April 9, 2024, as part of Microsoft's monthly Patch Tuesday cycle. It delivered crucial security fixes for Windows 11 23H2 and 22H2, addressing issues like elevation of privilege vulnerabilities and kernel flaws. But within days, user forums and IT support channels lit up with complaints about system freezes and boot failures. While Microsoft quickly acknowledged some of these problems, the full scope of the damage—particularly to backup software—didn't become clear until May. The update is now widely considered one of the most disruptive patches in recent Windows history, forcing many organizations to pause deployment.
2. A Surprising List of Affected Backup Tools
Reports from BleepingComputer and verified user accounts confirm that several industry-standard backup applications are crashing or failing after applying KB5083769. Affected programs include Acronis Cyber Protect Cloud, Macrium Reflect, NinjaOne Backup, and UrBackup Server. Even some enterprise-grade solutions have encountered issues, though the list continues to grow. Notably, these applications are not obscure—they are widely used by businesses and IT professionals for their reliability. The fact that a security update disrupts essential backup tools is a serious blow to disaster recovery preparedness.
3. The Real Culprit: A Bug in Volume Shadow Copy Service (VSS)
The root cause lies in a broken interaction between the update and the Volume Shadow Copy Service (VSS). VSS is a foundational Windows component that enables point-in-time snapshots of files, even while the system is running. Backup programs rely heavily on VSS to create consistent, disruptionless backups. According to experts, the KB5083769 update introduces a race condition or resource conflict in VSS that prevents it from properly handling snapshot requests. When a backup tool calls VSS, the service either hangs or returns corrupted data, causing the backup to fail or the application to crash outright. Microsoft has not yet confirmed the precise mechanism, but the pattern is undeniable.
4. Symptoms Beyond Backup Failures
The VSS bug doesn't just stop backups from running—it triggers a wider range of symptoms. Users have reported that attempting to launch a backup program causes the entire system to freeze for minutes, followed by error messages like "VSS writer error" or "Snapshot creation failed." In some cases, backup jobs that were previously scheduled quietly disappear from the queue. A few administrators have even observed that the error propagates to other VSS-dependent operations, such as System Restore points and disk management tools. This makes the update a double-edged sword: it fixes security holes but breaks reliability.
5. The Immediate Recommended Fix: Uninstall the Update
Until Microsoft releases a permanent patch, the only reliable workaround is to remove KB5083769 entirely. This can be done through Settings > Windows Update > Update history > Uninstall updates, then selecting the problematic update. After a reboot, backup software should function normally. However, this leaves your system exposed to the security vulnerabilities the update was meant to fix. IT administrators face a tough decision: risk security gaps or lose backup continuity. Many are opting to uninstall temporarily while monitoring Microsoft's response channels for a hotfix.
6. No Official Acknowledgment or ETA from Microsoft (Yet)
As of May, Microsoft has not publicly acknowledged the VSS-related backup issue on its official documentation or health dashboard. This silence is frustrating for IT teams who need clear guidance. Community support threads have been active, but there is no word on when a revised update (KBXXXXXXX) will be released. Based on past Patch Tuesday experiences, Microsoft may roll out a fix in the next few weeks—but there's no guarantee. The absence of communication adds uncertainty to an already stressful situation.
7. Impact on Business Continuity and Disaster Recovery
For organizations that rely on daily backups, even a short outage is dangerous. A corrupted backup chain can mean data loss if a disaster occurs during the gap. The affected tools—Acronis, Macrium, etc.—are often the backbone of disaster recovery plans. Without them, companies have to fall back on manual processes or alternate software, which may not align with their compliance or recovery time objectives (RTOs). Small and medium businesses are hit hardest because they lack the IT staff to quickly implement workarounds. This incident highlights the fragility of relying on a single OS update.
8. Prior Issues with KB5083769: A Pattern of Disruption
The backup problem is just the latest in a series of glitches linked to KB5083769. Earlier reports included BitLocker lockouts (where encrypted drives refuse to unlock), boot loops (especially on systems with certain hardware), and a Remote Desktop bug that prevents RDP sessions from connecting properly. Some users also experienced unexpected shutdowns. While these issues are separate from the VSS problem, they suggest the update was not thoroughly tested across diverse configurations. Microsoft's quality control for cumulative updates has been a recurring concern among IT pros.
9. Workarounds and Mitigation Strategies
Besides uninstalling the update, there are a few other approaches:
- Use Windows Server Backup or built-in Windows 11 backup features (which may also be affected, but less so).
- Block the update using the
wushowhide.diagcabtool to prevent automatic reinstallation. - Switch to image-based backups that don't rely on VSS—but that's a major shift.
- Isolate backup operations on a separate virtual machine that doesn't have KB5083769 installed.
Each workaround has trade-offs. The safest bet remains uninstalling and waiting for a fix. Check Item 1 for more on the update itself, or Item 5 for uninstall instructions.
10. What to Watch for Next
Stay tuned to the Windows release health dashboard for official updates. Be prepared to test any new patch in a staging environment before wide deployment. Also, consider adjusting your backup schedule so that critical backups are taken outside of Patch Tuesday windows. This incident serves as a reminder that even security updates can become vectors for operational risk. In the meantime, keep a close eye on community forums like BleepingComputer and Reddit for user-shared experiences and potential unofficial fixes. The situation is evolving, and a resolution should come within weeks—but patience is wearing thin.
In conclusion, the KB5083769 update has become a cautionary tale about the unintended consequences of even well-intentioned patches. While security must remain a priority, the disruption to backup software exposes a gap in Microsoft's update testing. For now, the best course of action is to remove the problematic update and diligently watch for a stable replacement. Your backups are too important to leave to chance.