Booting WIN10 from new cloned SSD

[amarknicholls]

I have successfully cloned my HDD containing Win10 to a new SSD. When I disconnected the HDD , the SSD clone booted as I'd expected. When I then re-connected my HDD intending to delete my old OS from it and use it for storage, Windows booted up from that instead of the new SSD. What am I doing wrong?

 

[amarknicholls]

Ok so now I'm blushing.....further investigation revealed I'd inadvertently disconnected the power supply to the SSD, which is now booting perfectly!...0-((