title: Error on trying to run a simple RPC program
body: <p>I am trying to run a simple RPC program which I have created using rpcgen. 
  Its a simple factorial program. This is my first RPC program. 
  The make works fine.Executables are also created. 
  But when trying to run the executables, I get this error: </p>
  
  <pre><code>$sudo ./fact_server 
  Cannot register service: RPC: Unable to receive; errno = Connection refused
  unable to register (FACTPROGRAM, FACTVERSION, udp).
  </code></pre>
  
  <p>I tried running the same program on another pc with the same OS (ubuntu). It runs perfect there. </p>