Why can't two SSD drives with different operating systems see each other?

Question

Windows

Previously, there was one SSD drive on which I used two OSes. Now I took another one, connected it, configured it (done formatting, created a volume). Then I installed two different operating systems on each drive (Win7, Win10). After installation, I found that when loading, it does not ask which OS the system should boot, but selects the one that was installed last. I opened the disk management menu, and there the second SSD is defined as a regular partition for writing files, and the second system is not indexed in the OS boot list. What to do? Maybe I forgot to configure something in the new SSD?

Disks

Answer 1

When did you install the second system, did you turn off the first boot disk?
Then you simply did not register the second axis on the second hard disk in the bootloader and you will have to do it manually.
here are some ways https://sonikelf.ru/spisok-zagruzki-operacionnyx-s...