Cannot find module 'internal/fs' after upgrading to node 7

First, open the console as administrator (or in the terminal with sudo if it is a Linux) and:

npm cache clean

For npm 5 and later

npm cache clean --force

Edit:

For windows you might fail to clean the cache, so you can remove the cache manually by deleting all the following folder content:

C:\Users\<USER-NAME>\AppData\Roaming\npm-cache

Thanks "superwf", this case might happen for some, but I never had to do this (maybe because of my lowest security level?!).

End Edit.

Then go back to the normal console (not administrator or root), return to your project directory where the package.json is located, and then delete the node_modules folder from your project, remove it completely, and then install node modules again inside your project folder:

npm install

You might need to update your modules before installing modules again. I recommend this, but be careful of breaking changes if there are any major version changes in your modules.This module npm-check-updates can help you to check the latest version and update them.

Also, you maybe need to install the latest global modules as well, check updates by:

ncu -g

or

npm outdated -g

If you're still stuck, you might need to remove the global node_modules folder and reinstall what you want again.

Edit:

Yarn option: Some people ended with the same issues even with the cleanup procedures, actually you save your time a lot using Yarn.Personally, I started to use yarn instead of traditional npm i, I can guarantee it is faster, and save your time, and your head from npm headaches.

In my case clearing the cache (OSX) did not work. I use n to manage node which causes npm to potentially be out of date. According to n docs you can update npm with:

curl -0 -L https://npmjs.org/install.sh | sudo sh

In linux，when I update to node 7, this happened, "npm cache clean" does work.

In windows, npm cache clean also generate

Error: Cannot find module 'internal/fs'

Just remove

C:\Users[username]\AppData\Roaming\npm

C:\Users[username]\AppData\Roaming\npm-cache

solved