title: MongoDB Error: couldn't connect to server
body: <p>I have a problem for a month and I did not find a solution.Both my laptop and PC have these problems(I started mongod before):</p>
  
  <blockquote>
    <p>Error: couldn't connect to server 127.0.0.1:27017
    src/mongo/shell/mongo.js:91 exception: connect failed</p>
    
    <p>Error: couldn't connect to server 127.0.0.1:27017
    src/mongo/shell/mongo.js:93 exception: connect failed</p>
    
    <p>Error: couldn't connect to server 127.0.0.1:27017
    src/mongo/shell/mongo.js:L112 exception: connect failed</p>
  </blockquote>
  
  <p>I have started the mongod process without any parameter.And also I have a reply message by pinging 127.0.0.1</p>
  
  <p>By the way I use windows os and It does not have any permission issue.
  In addition I started the data directory from scratch but did not work.
  (There is no error in mongod's log file)</p>
  
  <p>Any help ?</p>