[SOLVED] Replacement SSD for failed drive not booting

[OreoSalad]

My old SSD I used for my OS was failing. It was some offshoot 128gb drive that I literally only used to house the OS (Win10 Pro). I installed the drive, formatted and made a partition for the OS on the new drive. I then made a bootable USB device, booted the PC and installed Windows 10 to the partition with no issues. I removed the USB, turned the PC on, and got the "Reboot and select proper Boot Device or Insert Boot Media in selected Boot device" error. So I booted from the USB again, the partition shows up and shows that of the 100gb I allocated only something like 78gb was free. So clearly it wrote. So I put the original drive back in and booted, it boots and asks me which OS I want to boot to and lists 2. It boots to the new drive if I select it from there, and it shows up in DiskPart. I checked the BIOS and the drive is selected as the 1 boot priority. I'm stumped. Thoughts?

 

[CountMike]

My old SSD I used for my OS was failing. It was some offshoot 128gb drive that I literally only used to house the OS (Win10 Pro). I installed the drive, formatted and made a partition for the OS on the new drive. I then made a bootable USB device, booted the PC and installed Windows 10 to the partition with no issues. I removed the USB, turned the PC on, and got the "Reboot and select proper Boot Device or Insert Boot Media in selected Boot device" error. So I booted from the USB again, the partition shows up and shows that of the 100gb I allocated only something like 78gb was free. So clearly it wrote. So I put the original drive back in and booted, it boots and asks me which OS I want to boot to and lists 2. It boots to the new drive if I select it from there, and it shows up in DiskPart. I checked the BIOS and the drive is selected as the 1 boot priority. I'm stumped. Thoughts?

Do you have multiple drives in your system ? If yes check disk management, OS could have split boot partition between 2.
It's good practice to remove or disable all drives before OS installation specially if there's another OS or active/boot partition.
It's also good practice to let windows make all partitions it needs during installation to empty single partition, you can do partitioning later on.
Some backup utilities like Macrium Reflect free have an option to fix BOOT problems from it's rescue disk/USB.