Hello Mark Ambrose,
Thanks for the screenshots. I can see that Windows is still running from the old 238 GB drive, while the larger 1.86 TB drive contains the cloned installation as D:.
I would not change anything in System Configuration yet. That may only change the boot-menu entry, not which physical drive the computer starts from.
First, back up any files created or changed since the clone. Then:
- Shut down the computer completely.
- Temporarily disconnect the old 238 GB drive, Disk 1.
- Start the computer with only the 1.86 TB cloned drive, Disk 0 connected.
- If Windows starts, the cloned Windows partition should normally become C: automatically.
- Reconnect the old drive afterward, but keep the 1.86 TB drive first in the BIOS/UEFI boot order.
If Windows does not start with the old drive disconnected, reconnect it. That would suggest the clone’s boot files need repair, or the cloning process may need to be repeated.
The small A: drive is most likely an EFI system partition that was accidentally given a drive letter. Please do not format or delete it. Its drive letter can be removed later, once the correct boot drive is confirmed.
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