npm cannot install pm2 or nodemon in Windows 10

Question

I try to install a nodemon for the auto-restart nodejs server when my file has been changed. But I got two warnings so, I try to install other npm packages like forever or pm2, but I still get the same warning. Here is my warning capture:

Answer 1

Try,

npm cache clear -f 

and,

npm install pm2 -g --unsafe-perm