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EFI partition missing

Anonymous
2019-01-02T19:14:20+00:00

I bought a new SSD and did a clean installation of Windows 10 on the new drive, but i'm still keeping my old HDD into my laptop as a secondary drive.

After the installation worked (the laptop was working correctly) I decided to format my old HDD. After a reboot i got this message "default boot device missing, select a new boot device" but in the list there isn't any any element to choose. I booted from USB and checked with DISKPART from Prompt and there isn't any EFI partition in the SSD. I even tried with bootrec but it says "access denied" and the boot recovery tool isn't working either. My laptop can't boot and I can only use prompt. Can anybody help me?

Windows for home | Windows 10 | Install and upgrade

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  1. DaveM121 891.6K Reputation points Independent Advisor
    2019-01-02T19:21:29+00:00

    Hi Salvatore

    Was that HDD connected to your PC when you installed Windows 10 on the SSD?

    If so, there is a little known issue when installing Windows, if another drive is connected to the PC at the same time as Windows is being installed, the boot configuration, pagefile or EFI partition can end up on the wrong drive

    It is very important when installing Windows 10, that only the drive that Windows is to be installed on is connected during the installation, you can re-connect the other drive once the installation is complete

    Your only option is to re-install Windows 10 on the SSD . . .

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  2. Anonymous
    2019-01-02T19:51:42+00:00

    Hi Salvatore

    Was that HDD connected to your PC when you installed Windows 10 on the SSD?

    If so, there is a little known issue when installing Windows, if another drive is connected to the PC at the same time as Windows is being installed, the boot configuration, pagefile or EFI partition can end up on the wrong drive

    It is very important when installing Windows 10, that only the drive that Windows is to be installed on is connected during the installation, you can re-connect the other drive once the installation is complete

    Your only option is to re-install Windows 10 on the SSD . . .

    Edgy solution, but still a solution. Thank you a lot.

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    1 person found this answer helpful.
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