Start win7 from ext hd
I have win 7 on a bootable ext hd from a hp laptop. I like to rum windows from a another computer
I believe that is possible, but it would the same as booting linux from your usb. So you need to set you hdd into bootable mode or something like that. Many linux distributors give you guidances on it. Good luck.
PS: You would have to install windows onto your hdd, instead of your normal hard drive, therefore it would have to be disconnected.