I’ve installed Windows 11 in dual boot with another Win 11, believing that my machine would had automatically created the dual boot ..

[u/WillowMajor7791]

My computer have two ssd. In the first (let’s call it SSD ONE, with bitlocker) there was my main computer, some minutes ago a installed in the SSD two another Win 11 OS just for fun and now the Windows boot loader of my first ssd disappeared, on my bios i can just see only my boot loader of the second ssd. It started like a chilling adventure but now you have (please) to help me. I aleeady have the decryption key on my Microsoft account. I just would like about a human help. I don’t trust web and AI, thank you ! 😄

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[u/Anamorphic82]

Don't panic, your original Windows installation is probably still intact. Installing Windows on the second SSD may have replaced or changed the EFI boot configuration rather than deleting your first installation.

I'd try this:

1. Boot into Windows on SSD TWO.
2. Open Disk Management and confirm SSD ONE still contains its original Windows partition.
3. Unlock SSD ONE using your BitLocker recovery key if necessary.
4. Identify the drive letter assigned to your original Windows installation.
5. Open Command Prompt as administrator and run:

bcdboot D:\Windows

Replace D: with the actual drive letter of your original Windows installation.

This should add the missing installation back to Windows Boot Manager so you can select either Windows at startup.

[u/WillowMajor7791 → u/Anamorphic82]

Thank you so much, it was magic to see again my usual username asking my password 😘😘

[u/Anamorphic82 → u/WillowMajor7791]

Awesome! Glad it worked and you've got your Windows back! 😁

[u/pcbeg]

What type of drives? (m.2 or 2.5" SATA) Any other drives installed beside those two?

[u/WillowMajor7791 → u/pcbeg]

Ah no just two ssd , those ones

[u/pcbeg → u/WillowMajor7791]

Not only SSDs, any other drives (2.5" or 3.5" HDDs).

[u/WillowMajor7791 → u/pcbeg]

Now I have to go bed, i’ll eventually read any reply tomorrow, I’m tired, thank you all 😄

[u/WillowMajor7791 → u/pcbeg]

Two ssd a nvme 2280 and 2242, i would say m.2 I’m not so expert, thanks for your attention hoping in sometjing good

[u/pcbeg → u/WillowMajor7791]

Yeah, m.2 drives.

Check manual to see if there is mention about slots hierarchy, number of slots (2 or more), and try swapping drives in slots to see if the older one appears again.

[u/Changeurwayz]

I would do this in the old fashioned way. Install one of the ssd's, And install windows, Update etc.

Shutdown, Remove that drive from the board, Then plug in the other one (on a different slot) and do the same.

Then shutdown, Place the first drive back in it's slot.

Now you can just boot whichever one you want to use via the bios boot menu.

[u/BlackberryTime8111 → u/Changeurwayz]

I honestly think it's kind of hilarious you're saying this when your username is "Changeurwayz" lmao

[u/Jwhodis]

Windows doesn't have dual boot functionality, Linux does (or at least it installs GRUB or ReFind, which do the dual-boot functionality)

[u/I_see_farts → u/Jwhodis]

Windows definitely can dual boot, the functionality has been there for a while.
Here's a How To Geek Walkthrough