[SOLVED] [SOLVED] Wiped non-Windows drive and now Windows won't boot (BIOS only)

[HAMCORE]

Okay, here's the story.

I got a new SSD a couple days ago, and I moved my OLD SSD with Windows down one port (to M_2) and installed the new SSD to M_1.

I have an MSI MAG X570 TOMAHAWK motherboard and it would just go straight to BIOS with no Boot Manager. I tried bootrec via Windows 11 recovery drive CMD and it did not work.

So instead I installed Windows fresh on the new SSD in the M_1 slot, and got the files I needed over just fine. Once everything was transferred, and the PC was booting from the M_1 drive, I decided to wipe the M_2 (old Windows drive).

I just turned on my PC and it's doing the same thing. Straight to BIOS. This is Windows 11 and my BIOS does not have a Windows Boot Manager. I used AOMEI Partition Manager's recovery tool to try and fix the MBR but I noticed my old drive is now partitioned as the C: drive and my actual Windows installation was given the drive letter E:, which was formally occupied by another drive too? I'm at a loss. I don't want to have to reinstall Windows yet again.

UPDATE: Tried to bootrec /FixMbr and bootrec /FixBoot. These completed successfully. However, doing bootrec /RebuildBcd gave me an error saying "The requested system device cannot be found"

EDIT: A friend of mine pointed out that I probably deleted the EFI partition off of the M_2 drive. Since Windows likes to just use any EFI partition it finds, even if it's another disk. Now I'm looking for help to create and EFI partition (while shrinking a volume)

SOLVED!
I was able to use my bootable AOMEI disk to shrink a partition to let me create a new EFI partition via CMD in Windows Recovery. The guide I used is here and now my PC boots: https://answers.microsoft.com/en-us...tion-how/181745f9-3303-4968-9851-5c213db9c89c

 

[Lafong]

.......................Once everything was transferred, and the PC was booting from the M_1 drive, I decided to wipe the M_2 (old Windows drive)......................

I noticed my old drive is now partitioned as the C: drive and my actual Windows installation was given the drive letter E:,

I'm confused by the 2 above portions.

First part: when your "PC was booting from the M_1 drive" properly, was M_2 connected at that moment? Or not?

Second part: In the first part, you state you wiped the old drive.

If you did that, I don't see how "old drive is now partitioned as the C: drive".....because you supposedly wiped it.

Can you clarify?

 

[kerberos_20]

ye, that is normal, windows will put efi partition on first active master drive it finds

 

[HAMCORE]

I'm confused by the 2 above portions.

First part: when your "PC was booting from the M_1 drive" properly, was M_2 connected at that moment? Or not?

Second part: In the first part, you state you wiped the old drive.

If you did that, I don't see how "old drive is now partitioned as the C: drive".....because you supposedly wiped it.

Can you clarify?

Yea sorry, might have been a bad explaination. Essentially I just deleted/removed the EFI partition twice in 24 hours... It's fixed now though!