Q:

Error : npm install ERROR "No Valid versions available for dateFormat"? 

I use google cloud engine VM instances is CentOS7.  I clone the Node project from git and try to run but 

Error : Cannot find module 'dateFormat'

then I have tried to install dateFormat on CentOS7 with 

npm install dateFormat 

but display error this
npm ERR!  code ENOVERSIONS
npm ERR!  No valid versions available for dateFormat

npm ERR!  A complete log of this run can be found in:
npm ERR!      /root/.npm/_logs/2019-05-24T04_43_53_179Z-debug.log

How to fix them ? 

A:

Check your spelling of dateFormat, should be all lowercase
$ npm install dateformat

I just ran both on a vm centos7 with your spelling of uppercase F and all lowercase.  Using all lowercase works. 
see npm page https://www.npmjs.com/package/dateformat
while the require seems to use the uppercase F as
var dateFormat = require('dateformat');

the actual install package is all lowercase
If doesn't work try:
What version of npm are you running? 
Try removing and reinstalling npm
What project are you running from github?