Warnings Issued For Millions Of Microsoft Windows 10 Users - Forbes

In the meantime, Microsoft offers impacted Windows 10 users the following workaround, which is not for the fainthearted: 

• Restart the device, enter the BIOS
• Turn off Secure Boot, restart the device.
• In an administrative Command Prompt window, run:"%programdata%MicrosoftWindows DefenderPlatform4.18.1901-7MpCmdRun.exe" -revertplatform
• Wait for one minute, and then do the following:
• Run sc query windefend to verify that the Windows Defender service is running.
• Run sc qc windefend to verify that the Windows Defender binary no longer points to version 4.18.1901.7.
• Restart the device, re-enter the BIOS, and then turn on Secure Boot

That's no barrel of laughs, but given the Windows Defender flaw was widespread and potentially dangerous, it's clear Microsoft pushed out these fixes quickly. 

https://www.forbes.com/sites/gordonkelly/2020/03/28/microsoft-windows-10-warning-crashes-boot-problems-no-internet-wifi-upgrade-windows-10-free/ Warnings Issued For Millions Of Microsoft Windows 10 Users - Forbes