Windows 10: Dual booting windows 7 and 10

I have just upgraded windows 7 to windows 10...
I've bought a new ssd to install windows 10, but it was installed over my windows 7(in the old ssd) in the process....

Articles in this forum say that you cannot dual boot windows 7 and windows 10, since once you proceed to upgrade, windows 7 key is no longer valid....

If i roll back to windows 7, and install windows 10 using usb in a new ssd that i have just bought, will dual booting work?

And another question... Can i install two windows 10 system on seperate drive in the same computer?

:)

 

Dual Boot Change from Windows 8.1 & 7 to Windows 10 & 7

I have a dual boot Windows 8.1 and Windows 7.

(1) Is it possible to have a triple boot Windows 10, Windows 8.1 and Windows 7?

(2) If not, can I just upgrade the Windows 8.1 to Windows 10 to have a dual boot Windows 10 and Windows 7? Or do I have to do the normal dual boot set-up?

 

How do I restore dual boot capability after Windows 10 clean install removed it

My computer was dual-boot with Windows 7 boot partitions on two separate drives. After upgrading to Windows 10, the dual boot provision worked fine. However after a clean install of Windows 10, dual-boot capability is no longer available. The boot partition
for the remaining Windows 7 syBistem is intact. Only the dual boot option is gone.

I tried the changing the default operating system under System Properties/Advanced/Startup and Recovery, but the only choice is Windows 10. Windows 7 isn't a option. I'm guessing that the clean Windows 10 install wiped out access to the dual-boot menu.

Thanks.

Bill