Windows will not boot from new SSD

Question

I am trying to migrate my current C drive with Windows 10 installed (250GB M.2 SSD) to a 1TB M.2 SSD. Both are physically installed in my PC.

I used Macrium Reflect to clone the drive to the new SSD, which was successful as they were both identical (except the extra unallocated space in the new drive). I made sure that the new drive was GPT.

I then restarted, and in the boot menu changed the boot priority to the 1TB SSD, with the 250GB SSD as second priority. The boot mode is in UEFI.

However, it didn't work and when booting, the windows icon was still next to the 250GB SSD meaning it had booted from that drive.

I then opened my PC and physically disconnected the 250GB SSD. When I started up the computer again it gave me a "Recovery - your PC needs to be repaired" error, so obviously it was not able to boot from the 1TB drive at all and was going into recovery mode instead when it couldn't find the second priority boot.

I then reconnected the 250GB SSD, but instead of booting it in second priority, I disabled it in the boot menu. But this still didn't work and windows is still booting from this drive (evidenced by the windows icon next to it).

I am at a loss as to why even after disabling it in the boot menu it is still booting from this drive and why cloning, setting the new drive as GPT and ensuring it is booting in UEFI doesn't seem to be working. I've spent hours googling this and am at a loss! Any tips would be greatly appreciated!

Thanks

Answer 1

I found the solution to this. Special thanks to patkim - creating a new Boot entry wasn't necessary but it led me down the right path to finding the solution.

Side note: First I expanded the E drive since cloning with Macrium Reflect left most of the space on my new drive unallocated, defeating the purpose. To do this I used AOMEI Partition Assistant to merge the two, which was successful but modified the recovery partition on the new drive, making it a standard partition for some reason (I don't fully understand this). To fix this I simply deleted it and cloned the recovery partition from the C drive again using Macrium Reflect.

Onto the solution - I opened the command prompt as administrator, and ran bcdedit which showed me device and osdevice were still pointing to the current C drive. I modified both using the following two commands to point to e instead:

Bcdedit /set {default} device partition=e:
Bcdedit /set {default} osdevice partition=e:

Then I restarted. At first I thought it hadn't worked because running bcdedit showed them still pointing to the c drive, but the drive letters had been automatically swapped.

To test that everything was working from the new drive only I physically disconnected the old one and it worked.