I would just uninstall 7 and put on 10. The file format has not changed, so your old files should work properly. You can not have both running on the same box.
So which mean it is not possible to do a direct upgrade from 7 to 10. I need to uninstall my 7 before i can install my 10.
Well I am not 100% certain that it will not install on the same box ( I always unistall FMS on the box prior to upgrade ) . But considering that you can not run them at the same time, It just makes sense to uninstall it.