win10:
1. install emacs: https://www.gnu.org/software/emacs/download.html Windows
2. install aspell: http://aspell.net/win32/ Full installer
3. install dictionary: http://aspell.net/win32/	aspell-en-0.50-2-3.exe
4. add the folder of aspell to the $path: C:\Program Files (x86)\Aspell\bin
5. add the following to C:\Users\username\AppData\Roaming\.emacs
(setq-default ispell-program-name "aspell")