Now THIS is new: Cloned SSD does not boot – a new twist

Looked at many posts but did not find a solution.
I wanted to replace the original Kingston 500GB drive (m.2 PCIe) with m.2 WD 4TB SN850X.
Acer pc has one m.2 slot, and one PCIe 16 connector.
• Cloned disk with Macrium.
• Replaced old disk with clone – no boot. BIOS recognizes new drive (NVMe dev installed), but NSOD.
• Error code: Kernel security check failure. After three unsuccessful boot attempts get into Win rescue environment: Troubleshoot - Advanced Options – Startup repair – back to Kernel security loop.

And here comes the twist:
• Instead of using the m.2 slot for the cloned disk, I installed the clone – and ONLY the clone – via the PCIe connector. Lo and behold, the system boots!??
• BIOS does NOT recognize the SSD in the PCIe, but still boots.

• The usual culprits for a BSOD with Kernel security issues include bad disk, driver or memory issues, etc. Obviously this does not apply here, since the cloned disk boots and works fine in the PCIe slot, just not in m.2
• Both the old and the new SSD are M.2 PCIe

At this stage I am stuck: BIOS does not recognize the cloned SSD in the PCIe slot, yet Windows boots.
On the other hand, with the clone in the m.2 slot I get BSOD.
Any suggestion on how to make the new SSD bootable are very much appreciated!

Thanks for the suggestion. Don't think it's a hardware issue, otherwise it would not boot on PCIe either.

The system boots at least into the recovery environment!
What is the situation in the screenshot?
Disk 0 ==> PCIe adapter
Disk 1 ==> m.2 slot
Boot into Disk 1 (m.2 slot) and check if you have full access to Disk 0

You cloned the disk because the old was probably to small. Why don't you use both disks?
Did you check ACER for BIOS updates.
If my above suggestion works, just reformat the EFI-Partition from disk 0. (Do not delete that partition!)

Can I upgrade my Acer Aspire TC -895 PC's SSD M.2 2280 128gb to M.2 NVME SSD? — Acer Community

Aloha Pentagon,
Yes, Disk 1 is m.2, and disk 0 is on PCIe.
I do have full access to both drives in that scenario. However, the plan was to move everything to the large ssd and use the PCIe slot for a graphics card. In other words, I really prefer to be able to run with just the large disk.
Mahalo!

Megahertz said:

The computer is booting from the new 4T SSD as you can see on the Disk Manager you posted. C: is the partition with Windows and it is on the 4T SSD.
What is Disk 0 (PCIe or M.2)?


Install the new 4T SSD on the M.2
Remove the old SSD from the PCIe
Enter BIOS and make sure the 4T SSD on the M.2 is the first boot option.

Does it boot?

No, it doesn't boot. See post #1
@captainron
Make these changes:
WD 4TB SN850X ==> M.2 slot
Kingston 500GB ==> PCIe-adapter

Boot from PCIe (Kingston) (select in BIOS)
if (F:) = Win Installation drive letter on WD type otherwise use the right letter
C:\WINDOWS\system32>bcdboot F:\Windows

The command adds a boot-entry to the Kingston BCD
If it doesn't boot from that BCD-Entry, it's a Windows problem
If it boots it's a BCD problem on the WD
The additional bcd-entry can be removed again later.