2 HDD's How to change which one boots - missing 'NTLDR'

[Marse]

I'm trying to sort out four HDD's in my old PC before sorting out a new build.
OS on a 1 TB HDD trying to move to 500 GB.

Using Acronis True Image created Image of OS.
Full format of partition on 500.

I used Acronis bootable CD to format the system partition on the 1 TB.
I restored the Image to the first partition on the 500.
The PC wouldn't boot with a prompt saying missing 'NTLDR'.

I restored the same Image to the original partition on the 1 TB and now everything works.
I now have a partition on each HDD one marked as System one marked Active.
Both seem to have the same files present including C:\NTLDR but I can't boot from the one I want to.

I've now stopped tinkering since don't want make things worse, at least at the moment it works.
I'll need this PC working whilst sorting any issues that arise with the new one.

I want to leave the 1 TB unit in situ until I'm ready and don't want to risk putting it into the new PC as it is, in case it causes problems there where an SSD will be the boot drive.

Advice please

 

[Ivyforce]

select 'hard drive priority' in the bios, you should be able to select the order from there which disk you want booted 1st.

 

[Marse]

Thanks - I thought about that but when the 500 was the only drive with an OS on and it says 'missing NTLDR' I didn't think the priority would matter.

 

[Marse]

Swapped the leads around with the 500's on 0 & 1 - "operating system error" and won't boot.

Put leads back as they were and now running on the original OS on 1 TB drive.

Thinking..........

 

[Marse]

select 'hard drive priority' in the bios, you should be able to select the order from there which disk you want booted 1st.

I will never doubt you again

Thank you