You need to be careful while selecting between relative and absolute path names in the class paths. You need to be least concerned about it, as system classes automatically find their location and you don’t have to do anything about it. This oneHOWTO article is going to give you detailed information on what does this error message mean, what are its causes, and how you can fix it. We are trying to execute this class using the command line. There may be several reasons that may cause this error message to appear on your screen. Initially, you can start by checking the class name and the class path settings. For a deeper understanding of this concept, you need to learn some information about class path as well. If you are a new Java developer, you must have seen the ‘could not find or load main class’ error, after which your programs refuse to run. In order to check that, find out the correct name of your package because you have placed your main class in that package. You did not enter the class name correctly. Even if you specify the class name in the right way, Java command may not be able to find the needed class. If the FQN of your class is com.acme.example.Toon, then JVM will look for Toon.class inside the directory. Let’s talk about them in detail: 1. You specified incorrect class path for the application. Make sure that you have written the right program and its class name. You declared the class in wrong package. Main class defined in the manifest.mf file and … While executing, when JVM does not find a .class file with the specified name then a run time error occurs saying “Could not found or load main class” error as − D:\sample>java Example Error: Could not find or load main class Example Caused by: java.lang.ClassNotFoundException: Example There are many ways Error: Could not find or load main class HelloWorld manifests itself, but if you know the basics of Java Classpath, you can easily sort out the problem. If that’s done fine too, then you can import the related language program and compile it. That’s the only way we can improve. It occurs when we try to run a program. Renaming the class by shifting its position won’t help either in this case. MainClass.java. The error indicates that the java command failed to find or load the main class. But some of the most popular and common errors are often faced by programmers who are new in programming. Here are a few examples: 2. In order to resolve the error problem, you need to identify its cause first. 1. Java is a relatively easy language program to learn and operate. Class is located in the structure of the directory just below that root, and you can find it by providing a completely qualified name to your path name. There can be several different ways of providing a wrong class name. One of the most common reasons is that you did not provide the correct class name, or you provided the right class name with some mistake. When you receive this error message, this simply means that the system has failed during the first step itself. However, the ‘could not find or load main class’ error message right in the beginning of running it can be frustrating and discouraging. If you did this in some IDE, then its compiler will alert you about it immediately. If everything seems fine and there is no spelling mistake, then check that you have set the path correctly. By the way, there are more to it e.g. If that’s correct, the next thing you need to look into is the class path. 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In order to correctly load the main class, the JVM finds the following: Please note that JVM and JLS specifications leave some space for JVM to load the classes, and it can have some effect on when it throws the class loader exception. All Rights Reserved. If you want to read similar articles to Could Not Find Or Load Main Class – What Does It Mean?, we recommend you visit our Software category. We get this error because we are incorrectly trying to run the main () inside the class using java command. Most of the time you just need to either correct your CLASSPATH environment variable or run your program with java-cp or -classpath option. Let’s talk about them in detail: 1. There may be several reasons that may cause this error message to appear on your screen.