[SOLVED] Windows 10 won't boot from a new M.2 drive

[vagr]

I have just built a new PC, now I am trying to transfer my windows 10 from an old ssd to one of my two new M.2 drives.

I have tried cloning but it didn't work, so I instead created a system image of the old ssd and installed a fresh Windows on the new M.2. After doing this, and taking out the SSD, I realized that the fresh windows install won't boot from the new M.2. It does not show up as a bootable option in BIOS at all, it does show up in storage, but is simply not bootable.
When I boot with my old SSD, it lets me choose which system I want to run, whether the windows from the old SSD or windows from the new M.2, but I have to boot with the SSD for this option to come up.
It's important to note that when I tried to install Windows from a flash drive to the M.2, I kept getting an error when I tried to choose this drive to install windows. I first had to insert the SSD to even be able to install the Windows to the M.2 for some reason.

The drive is otherwise behaving normally as one would expect. WD Dashboard shows that the drive is healthy and behaving normally.

My specs are:

MB: MSI B550 Tomahawk
Drives: 2x WD Blue SN550 NVMe SSD 1TB
RAM: Kingston HyperX Predator DDR4 16GB 3600MHz CL17 DIMM 1.35V
PSU: Seasonic FOCUS GX-850 Gold, 850W
CPU: Ryzen 5800x
GPU: RTX 3080

Can someone please tell me what is going on here? I have been trying to make this work for two days now, scoured the internet for answers and found nothing that would help. The only thing I found was one amazon review that mentioned difficulty cloning the drive, but ultimately suceeding with a fresh windows install and restoring system image .

 

[USAFRet]

The fresh install on the new drive needed to be done with ONLY that drive connectred.

Disconnect all other drives, and redo the OS install.

Outlined in the first part of here:

How To - Windows 10 clean install tutorial

If you are looking for the Windows 11 Clean install tutorial, you can find that here: Windows 11 Clean install tutorial (Click here) Otherwise, welcome to the Windows 10 Clean install tutorial This tutorial is intended to help you, step by step, to perform a clean install of Windows...

forums.tomshardware.com

 

[vagr]

Thanks, will try and report back.

 

[vagr]

I have tried it now, it is not possible as it wont let me. It gives me an some disk partition error. I have now forgotten the exact error as i have now ruined my old ssd drive and am a bit stressed.

 

[SkyNetRising]

It gives me an some disk partition error. I have now forgotten the exact error as i have now ruined my old ssd drive and am a bit stressed.

Be specific. This error is important, if you wish to resolve it.

Generally it's enough to clean drive before installing windows, to resolve any partitioning format errors.
This can be done with diskpart.

 

[vagr]

Be specific. This error is important, if you wish to resolve it.

Generally it's enough to clean drive before installing windows, to resolve any partitioning format errors.
This can be done with diskpart.

Thank you for the help. The problem is now solved.

The issue was that I already formatted the M.2 drives and I didn't realize that this would block the Windows installation. Cleaning the drive with diskpart helped and I was able to install windows just fine without the SSD plugged in. It now boots windows as it should.