build path error

Description Resource    Path    Location    Type
Project 'OpenHybridSim' is missing required Java project: 'ipss.plugin.multiNet'    OpenHybridSim       Build path  Build Path Problem
Project 'OpenHybridSim' is missing required library: '/ipss.lib.3rdPty/lib/cache/hazelcast-3.5.jar' OpenHybridSim       Build path  Build Path Problem
