boot failled

Hi, I have a Samsung 860 Pro 256GB SSD and a Western Digital Ultrastar 4TB HDD installed on one of my PCs which I named it as PC1 The issue that I’m facing is that when I tried to replace either one of them to a new exactly same type of SSD/HDD, the PC will display this error: Default boot...

I Recently took apart my dell latitude e6420 apart , everything was ok until I put it back and booted it up and to my shock they say no boot drive is detected , when to check the If it was properly installed and it was , went back to BIOS and to my shock they say there is no HDD whatsoever even...