Microsoft’s June 2020 Patch Tuesday Windows 10 KB4557957 and KB4560960 patches cause flash reboots and Local Security Authority Subsystem Service (LSASS) to crash
KB4557957 and KB4560960 patches that are meant to fix the May 2020 Windows 10 2004 issues are themselves causing flash reboots for many users. The KB4557957 and KB4560960 patches were released by Microsoft on Patch Tuesday as a part of its June 2020 updates are also known to cause the crash of the Local Security Authority Subsystem Service (LSASS) on Windows 10 PC/laptops.
Local Security Authority Subsystem Service (LSASS) for Windows 10 is a very vital cog for providing cybersecurity to Windows 10 run PCs/Laptops and servers. LSASS is responsible for enforcing the security policy on the system. It verifies users logging on to a Windows computer or server, handles password changes, and creates access tokens. It also writes to the Windows Security Log and details the security information. Because lsass.exe is a crucial system file, its name is often faked by malware. The lsass.exe file used by Windows is located in the directory %WINDIR%\System32.
When LSASS fails, the user will immediately lose access to any accounts available on the machine, an error will be displayed, and the machine is forced to restart.
Many users reported the issues with KB4557957 and KB4560960 patches. In separate bulletins, Microsoft says that these two patches were released to fix the No Printer issue that Windows 10 PC/laptop users were facing. Windows 10 2004 caused some PC/laptops to not recognize many brands of printers like HP, Canon, etc after the update.
The Windows 10 KB4557957 and KB4560960 patches seem to affect all Windows 10 PCs/laptops from version 1809 to 2004. One user noted that,
We have some machines on our domain that’s crashing upon login. They get the “Your PC Will Automatically Restart in One Minute” then they are forced to restart. After the restart, they’re able to login again and continue working until the next day. Machines affected are running Windows 10 1809 with the latest patches. Event Viewer Log shows that LSASS.exe crashed on the first boot with error c0000008 and then all services failed to authenticate after, which probably caused the crash. “A critical system process, C:\WINDOWS\system32\lsass.exe, failed with status code c0000008. The machine must now be restarted.”
Another user stated that his Windows 10 1809 Enterprise version went into a reboot loop after downloading the Patch Tuesday patches.
Microsoft has not yet acknowledged the issues faced by Windows 10 users downloading KB4557957 and KB4560960 patches. As of now, there are no workarounds other than removing both these patches from your PC/laptop/servers. You can uninstall them as below:
Go to Settings>Updates or type update history in the search window and select View your Update history. Select Uninstall Updates. Go to Installed Updates findKB4557957 and KB4560960, and select the Uninstall button.
Once uninstalled, restart your computer and you have got rid of the flash reboot/LSASS crash problem.