title: Class "simpleModule" not found in omnetpp
body: <p>I am writing my own simple modules in omnet++.</p>
  
  <p>Inside the omnet IDE, I have created three simple modules.</p>
  
  <p>After that I have created a "network" using those modules.</p>
  
  <p>It is building successfully, but whenever I try to simulate it it shows</p>
  
  <blockquote>
    <p> Error in module (cModule) NetworkTopologyOnly (id=1) during network
    setup: Class "mySimplemodule2" not found -- perhaps its code was not
    linked in, or the class wasn't registered with Register_Class(), or in
    the case of modules and channels, with
    Define_Module()/Define_Channel().</p>
  </blockquote>
  
  <p>What should I do to successfully simulate using my own simple modules?</p>