NPM ERR Code E401: Unable to authenticate, need: Bearer authorization
Solution 1:
This is what worked for me.
First, delete the .npmrc file in your Users folder. This folder:
C:\Users\[your user name]
Then run this command in your project folder that has an .npmrc file in it:
npx vsts-npm-auth -config .npmrc
Solution 2:
Use npm install --registry https://registry.npmjs.org instead of npm install