Unable to start-up the Mendix project from Eclipse

Hi, I followed the steps from : https://world.mendix.com/display/refguide6/Using+Eclipse. But when i try it to launch from eclipse i m getting following error:

Error: Could not find or load main class com.mendix.m2ee.server.M2EEServer

I m using Eclipse Mars SDE J2EE.

Not sure what i m missing here.

Thanks, Swathi S