I have just done this again, new Eclipse workspace on the previously fresh computer. I started by deleting C:\Users\Phillip\.m2 to attempt to get it back to perfectly clean. Then I opened a new Eclipse workspace and cloned the projects from Github. I right clicked on the Core\pom.xml and did a Run As... --> Maven Install. I had to set / add my JDK again in Eclipse, through Window --> Preferences --> Java --> Installed JREs, (as well as the nested "Execution Environment" panel for JavaSE-1.8 and 1.7). Then I got some errors about Jars when running the maven install after setting the JDK. So, I did a Run As... --> Maven Clean on Core\pom.xml. Then I closed Eclipse, then deleted C:\Users\Phillip\.m2\repository. Then opened Eclipse into that workspace again, right clicked on Core\pom.xml, Run As... --> Maven Install ... success! Debug configurations.... Java Application --> New, selected project CoreBundle, did a search for Main classes, com.serotonin.m2m2.Main was right there in the list. Selected that, added the -Dma.home="C:\IA\Instance4\ma-core-public\Core" VM argument and started Mango.