The recent kaspersky Anti-Ransomware Tool UPDATE left twelve Windows 8.1 and Windows 10 workstations unbootable with bluescreens requiring backup image restoration. In those that would boot, the update broke Shadow Copies leaving System restore unusable and Image backup programs like Macrium Reflect broken.
Symptoms: Blue Screen, Windows Unbootable, System Restore Broken within Windows (See: https://www.thewindowsclub.com/system-restore-error-code-0x81000203 ), corrupt critical system files and services (digital signature errors: XXX service which failed to start because of the following error: Windows cannot verify the digital signature for this file. A recent hardware or software change might have installed a file that is signed incorrectly or damaged, or that might be malicious software from an unknown source.)
Resolution: System Restore using a bootable USB such as Windows Recovery Drive.
Resolution: Restoring Backup Images
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