What If You Cut Power Mid-Update?
Windows stages an update beside the old system and only switches over at the end, so a power cut usually rolls back. The firmware has no second copy.
The script
Your P C is halfway through an update... and you hold the power button.
That should destroy it. Usually, it doesn't.
Windows doesn't write over the old files. It stages the new ones beside them.
Cut the power before the last step, and the next boot rolls back.
Android keeps two copies, A and B, and updates the one you're not using.
If it fails, the phone boots the old one.
But one update has no second copy. The firmware.
Cut the power during a B I O S flash, and the board is gone.
So the next time that bar is stuck at forty seven percent...
The facts, checked
- Windows Update stages updates offline through the servicing stack and commits them during a restart; the component store keeps the previous versions, so a failed update can roll back. Re-check this wording against Microsoft's servicing documentation before publishing.
- Android A/B (seamless) updates write to the inactive slot; the bootloader switches slots only after the update verifies, and a failure falls back to the working slot (source.android.com, A/B updates).
- UEFI firmware updates are applied as a capsule with no second copy on most boards, so a power loss during the flash can leave the device unbootable; dual-BIOS boards are the exception.
- Do not say "your PC can never be bricked": a power cut during a firmware flash, or a corrupted bootloader, is the real risk.
