Error : couldn't connect to server 127.0.0.1:27017, connection attempt failed : Socket Exception

In this post : Error: couldn't connect to server 127.0.0.1:27017 - #4 by Stephen_Fuller it says I need to create some directories because me too when I run the command : " netstat -an | grep 27017` " I don’t get any output. But I don’t know what I have to do since it is not stated clearly in the other post