Well, there were Microsoft updates that did make all your files inaccessible.

Try doing the Windows 10 anniversary upgrade if you run bitlocker and have customized your UEFI.

Windows will screw up, bluescreen, and destroy the bitlocker keys.

I’ve fought with that before.

Out of curiosity, what customizations did you make to your UEFI setup? I run BitLocker and did the Anniversary and Creators updates without issue.

I don’t actually ever invoke any bootloader directly, but instead use an EFI app which in turn loads the bootloaders.

Windows’ Anniversary Update works by adding an additional, hidden EFI bootloader, and loading that for the upgrade.

If you instead load the normal Windows EFI bootloader while the upgrade has half-way finished, then it fucks stuff up.

I’ve been through it multiple times, last time, Windows even destroyed all its own EFI entries.

Microsoft literally pushed adware and spyware on Win7/8 users.

Are you talking about the telemetry stuff? Because that's a loaded way to describe it.