Windows 10 and Windows 7 on same system with same product key?

[Mangelwurzel]

Will this work or will there be issues?

Keen to keep Win 7 and also give Win 10 a shot before the free upgrade finishes.

I was thinking of unplugging my Win 7 drive, adding another drive to the system, installing Win 7 on it, then upgrade it to Win 10. That way I can leave the original Win 7 drive untouched.

 

[Disco_P]

I think i did something similar with Windows 8.1 and 10. I did it on the same physical disk with partitions.

I installed 8.1 fresh alongside my old install. Upgraded the new one. Installed 10 fresh alongside the old 8.1 install. Both worked fine but I rarely used 8.1 after 10 so don't know of any long term side effects.

 

[linktoinsanity]

I have this on mine, running a dual boot of Windows 7 Professional and Windows 10 Professional off the same Retail key. The reason I don't see a problem license wise is as follows:

How many computers is it installed on? One
How many computers use the same key at the same time? One

So I do not see it as being against the license terms. Maybe someone else can clarify?

 

[mahius]

I plan on doing the same. The good news is that I've got a spare key via a Windows 8 tablet I've not upgraded if it doesn't work. I might be able to nick the key from that, via command prompt.