It is possible to install WMP 9 on Windows 7 but according to what I read you have to hack the installer files with Resource Hacker. I saw this video on You Tube and several others where some people managed to get WMP 9 working on Windows 7. But it is a complicated process and it did not work for me. See this video I found on You Tube here-
http://www.youtube.com/watch?v=yp7qmclz5fI
I think you would have to do the same thing for WMP 10. And I have not been able to install either on Windows 7, not even by copying the WMP 9 and WMP 10 program files from my Windows XP computer,no.
But I do however have WMP 11 on both my Windows 7 and Windows 8. But it is WMP 11 for Windows 7 which is version of WMP 11 that someone made adapted to run on Windows 7. I found out about it from here-
http://www.youtube.com/watch?v=40OJ4Gtvvnk
And I now have WMP11 on Windows 7 and Windows 8. Andrea Borman.