cash: [Windows 10] npm install cash-global -g does not work

1. npm install cash-global -g
2. Restart pc
3. 'ls' is not recognized as an internal or external command, operable program or batch file

However when I do cash it works as before. Am I missing something?

C:\Users\stani>node -v
v5.9.1
C:\Users\stani>npm -v
3.8.3