I had SSD added to my laptop rig, next to an existing HDD with Windows 7. There is Windows 10 installed on SSD and it boots immediately when I power laptop on. I get no option to boot Windows 7, furthermore I can't see HDD in BIOS Boot Priority List.
It does show up elsewhere in BIOS and I can see all files on HDD from Windows 10. How do I get BIOS to recognize my HDD as bootable again?
22 Answers
After spending considerable time tinkering, I discovered my BIOS does in fact support UEFI via enabling/disabling CSM mode. It makes no difference. BIOS/UEFI sees my HDD but not as a bootable device.
I suspect my hardware supports only one bootable SATA connection, and of course SSD was hooked to that one. Luckily, I still had bootable USB stick for Windows 7, so I booted from it and used the Repair function. It found Windows 7 on my HDD and added it to boot records on the SSD (here I don't know the absolutely proper terminology). Bottom line is SSD is now main boot device and it "knows" about my Windows 7 installation on HDD.
Hope this helps anyone who would end up in a similar situation.
- Maybe we need to disable the setting like "Fast Boot" or "Secure boot" or other similar name in BIOS, the BIOS settings are different depending on the model of the machine, we can search it online if we can find the setting. Then we may see legacy boot (it is also called "MBR boot") and UEFI boot.
- We go to see if HDD will show up in BIOS Boot Priority List, if so, we can set SSD or HDD as a priority start item according to our requirement.