PinkConnectMark

Hi @secured2k,
Thank you for getting in touch, here is the KB that you requested regarding the ESET Windows Updater Utility: https://support.eset.com/en/kb7148-manually-install-windows-10-feature-updates-on-a-full-disk-encrypted-fde-system
The error you are running into is due to the disk not being accessible during the update as it is Encrypted and Windows has not been told to use the Encryption Drivers in order to access the disk, this utility solves that problem by passing the required switches to allow Windows to use the Encryption Drivers and thus be able to access the disk.
Thanks,
Kieran 

Hi @secured2k,

Here is a KB with some more technical details about what the tool is doing: https://support.eset.com/en/kb7394-technical-details-regarding-eset-endpoint-encryption-and-windows-feature-updates it also explains how you can do this via the WSUS method, providing the relevant Microsoft articles required to do this.
The problem is that the driver is not available in the Windows installation image. Windows Feature updates contain a .wim image which uses windows RE (Recovery Environment).
During the update the system boots to this image to perform the upgrade of the OS. This environment does not automatically use any extra drivers.

What we do to perform the upgrade is use a feature of the setup to “reflect” the drivers through to the installation image:
Setup.exe command line switches - This is how the ESET Endpoint Encryption Windows Feature Updater Utility does it SetupConfig.ini - This is supported by Windows Update or WSUS