Mongodb failed to connect to server on first connect

Question

I get the following error   Warning   MongoError  failed to connect to server  mongodb 27017  on first connect     at Pool  lt anonymous gt    Users michaelks Desktop users node modules mongodb-core lib topologies server js 325 35      at emitOne  events js 96 13      at Pool emit  events js 188 7      at Connection  lt anonymous gt    Users michaelks Desktop users node modules mongodb-core lib connection pool js 270 12      at Connection g  events js 292 16      at emitTwo  events js 106 13      at Connection emit  events js 191 7      at Socket  lt anonymous gt    Users michaelks Desktop users node modules mongodb-core lib connection connection js 173 49      at Socket g  events js 292 16      at emitOne  events js 96 13      at Socket emit  events js 188 7      at connectErrorNT  net js 1025 8      at  combinedTickCallback  internal process next tick js 74 11      at process  tickCallback  internal process next tick js 98 9    name   MongoError     message   failed to connect to server  mongodb 27017  on first connect      Even though I get this in the terminal window where I run Mongo   2016-12-25T03 45 23 715 0100 I NETWORK  initandlisten  connection accepted from 127 0 0 1 58868  8  8 connections now open     It kinda looks like there is a connection    I ve tried both    mongod    and    brew services start mongo    This is my test helper js  const mongoose   require  mongoose    mongoose connect  mongodb localhost users test    mongoose connection   once  open        gt  console log  Good to go       on  error    error    gt     console warn  Warning   error          I have not specifically made the db  users test  as I am under the impression that mongoose or mongo or both will do this on the fly   I ve tried both  localhost  and  127 0 0 1    I m on OSX 10 11 5 I m running Node 7 3 0 and Mongo 3 2 9  What am I doing wrong  How do I figure out what s wrong