Migration
Clone the disk Windows boots from—without surprises
Updated May 2026 · 11 min read
Cloning copies blocks, not intentions. Your firmware still needs a valid EFI system partition or MBR bootstrap, and the destination must be large enough for used space plus growth headroom.
Match firmware story to disk layout
UEFI machines expect GPT disks with an EFI system partition. Legacy BIOS often expects MBR boot code. Mixing stories without a reinstall plan causes the infamous boot loop.
If you convert styles, do it deliberately with the product documentation you trust, not as a side effect of a midnight clone.
Capacity and sector size
Used space on the source must fit inside usable capacity on the target after any hidden OEM partitions you plan to keep.
Advanced Format drives sometimes expose different logical sector sizes—cloning tools usually handle alignment, but verify with the product FAQ if cloning between mismatched generations.
Verification beats bravado
Boot the clone while the original disk is still present but disconnected or disabled in firmware, not just unplugged halfway.
Log into Windows, open Disk Management, confirm drive letters, then shut down cleanly before repurposing the old disk.