title: Unsupported major.minor version 52.0 captive portal
body: <p><strong>Hi guys,
  I have to make a captive portal for a school project with some friends. One of us got it working and we basically copied the image from his Raspberry PI to our Raspberry PI. After we did that, everything seems to be fine but then suddenly when we open our Captive Portal and try to log in with the username and password which we have saved in the database, this appears:</strong></p>
  
  <p>HTTP Status 500 - captiveportal/proccess : Unsupported major.minor version 52.0 (unable to load class captiveportal.proccess)</p>
  
  <p>type Exception report</p>
  
  <p>message captiveportal/proccess : Unsupported major.minor version 52.0 (unable to load class captiveportal.proccess)</p>
  
  <p>description The server encountered an internal error (captiveportal/proccess : Unsupported major.minor version 52.0 (unable to load class captiveportal.proccess)) that prevented it from fulfilling this request.</p>
  
  <p>exception</p>
  
  <p>java.lang.UnsupportedClassVersionError: captiveportal/proccess : Unsupported major.minor version 52.0 (unable to load class captiveportal.proccess)
      org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:2905)
      org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:1170)
      org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1678)
      org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1556)
      org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:461)
      org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
      org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
      org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
      org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1002)
      org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:579)
      org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
      java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
      java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
      java.lang.Thread.run(Thread.java:745)
  note The full stack trace of the root cause is available in the Apache Tomcat/7.0.28 logs.</p>
  
  <p><strong>We basically need to fill in the username and the password and after that we should be able to use the internet but unfortunately this error appears.
  Did somebody have got the same error before? I am not sure what to do, I kept searching for straight 2 days but unfortunately I couldn't find the answer.
  I hope you guys can help me with this problem, thanks in advance.
  Empaier.</strong></p>