I need to re configure my hard drives

Mark Ambrose 0 Reputation points
2026-07-31T20:06:10.4733333+00:00

I have had to change my hard drive c for a bigger one but I cannot get my system to change it. At the moment I have Drive D which is my new drive and drive c which is my old D drive. I also have Local disk A I do not know where that has come from, as it has also locked me out refusing me permission, even though I am the only Administrator on my PC.

So the question is how can I sort out these drives and get my self running properly again. The D drive is the one which I cloned from my old C drive.

Many thanks look forward to an answer.

Screenshot 2026-07-31 210126.png

Screenshot 2026-07-31 205453.png

Windows for home | Windows 11 | Files, folders, and storage
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  1. Thomas4-N 20,870 Reputation points Microsoft External Staff Moderator
    2026-08-01T06:22:20.4+00:00

    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:

    1. Shut down the computer completely.
    2. Temporarily disconnect the old 238 GB drive, Disk 1.
    3. Start the computer with only the 1.86 TB cloned drive, Disk 0 connected.
    4. If Windows starts, the cloned Windows partition should normally become C: automatically.
    5. 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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  2. Craig Long 18,520 Reputation points
    2026-07-31T21:44:27.56+00:00

    Is your drive D: a solid-state drive? I do not advise running Windows on a hard disk drive.
    First, I suggest changing the boot order in the BIOS. I can't give you specifics on how to do that on your particular device.

    Maybe A is a system recovery drive (partition) that somehow got a drive letter attached to it? Others can jump in with ideas.

    Also try this: In the Windows Start menu, type "System configuration" and select it. On the window that opens, click the "Boot" tab. If Windows on drive D is shown, select it and click "Set as default". Then reboot your computer.

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