Metrofile Cloud Backup & Protect - Backup Failures from Microsoft Update KB5083769

Update timeline

1. identified May 06, 2026, 10:54 AM UTC

   Dear valued Resellers and Customers, We are currently tracking a known issue following Microsoft’s April 2026 security update (KB5083769). This update is causing backup failures across multiple backup platforms. THE ISSUE The Microsoft update blocks a specific vulnerable kernel driver used for managing backup images. This results in Microsoft VSS timeouts during the snapshot process. • Error Message: "The backup has failed because Microsoft VSS has timed out during the snapshot creation." • Scope: This is a broad Windows 11 issue affecting multiple backup vendors; it is not a security vulnerability within Acronis itself. CURRENT STATUS & WORKAROUNDS • Official Guidance: Microsoft does not recommend a broad uninstallation of this security update. • Risk-Based Decision: If backups are business-critical on an affected system, you may consider temporarily deferring or removing the update. This should be evaluated as a short-term, risk-based workaround until a permanent fix is released. • Resources: Microsoft KB5083769 https://support.microsoft.com/en-us/topic/april-14-2026-kb5083769-os-builds-26200-8246-and-26100-82… • Acronis Support KB Article https://care.acronis.com/s/article/Acronis-Cyber-Protect-Cloud-Backup-fails-with-The-backup-has-fai… OUR ACTION PLAN Our team is actively monitoring backup statuses across all managed platforms. If you detect the VSS timeout error on your systems, please contact our support team immediately so we can document the impact and assist with manual remediation. COMMUNICATION We will revert with any feedback from Microsoft to install the new KB that gets released to fix the VSS timeout and backup failures. Please reach out to [email protected] for any support or queries.

2. monitoring May 18, 2026, 10:21 AM UTC

   Microsoft has confirm that their recent update has resolved the VSS issue affecting Windows 11 machines backing up with Acronis. Please update your systems to KB5089549 released on the 12th of May, and run a test backup. https://care.acronis.com/s/article/Acronis-Cyber-Protect-Cloud-Backup-fails-with-The-backup-has-failed-because-Microsoft-VSS-has-timed-out-during-the-snapshot-creation-after-installing-Windows-11-update-KB5083769?language=en_US Please contact [email protected] for additional information or if the issue persists.

3. resolved May 27, 2026, 02:11 PM UTC

   VSS Writer issues have been resolved with the latest Microsoft Update, we are happy that client systems are backing up. If you are still having issues backing up, please contact [email protected] to assist.