I want to switch from windows 7 to 10, however when I did it messed up all my windows live mail, so went back to 7.. How do I download 10 again without all the windows mail issues?

I downloaded windows 10 awhile back and had a nightmare regarding my windows live mail account. Folders were lost, folders were duplicated, email sending and receiving issues. So I went back to windows 7.. Now time is getting closer that downloading windows 10 won't be for free. So how do I download it again, without having all the same issues with windows live mail???  Please help.