Hello, this is regarding issues such as Main class not found or Can not find symbol while executing or compiling. You just need to set proper path of your cloudsimsdn directory. I stored CloudSimSDN folder downloaded from github at location E:\ with the name cloud. It's very much important to provide proper jar file's address as well as providing complete path of file that has to be inputed such as energy-physical.json. Set Java path variable value: C:\Program Files\Java\jdk1.8.0_121\bin CLASSPATH value : E:\cloud\jars\*; E:\cloud\src; For Compiling javac E:\cloud\src\org\cloudbus\cloudsim\sdn\example\ SDNExample.java For Executing java org.cloudbus.cloudsim.sdn.example.SDNExample MFF E:\cloud\dataset-energy\energy-physical.json E:\cloud\dataset-energy\energy-virtual.json E:\cloud\dataset-energy\energy-workload.csv > results.out These commmands are tested with Windows 10 and Latest java version. Please share your valuable comments and queries....