Exception in thread "main" java.lang.NoClassDefFoundError: HelloWorld
If you receive this error, java cannot find your compiled byte code file, HelloWorld.class.If both your class files and source code are in the same working directory and if you try running your program from the current working directory than, your program must get executed without any problems as, java tries to find your .class file is your current directory. If your class files are present in some other directory other than that of the java files we must set the CLASSPATH pointing to the directory that contain your compiled class files.CLASSPATH can be set as follows on a Windows machine:
a. Click Start > Right Click "My Computer" and click on "Properties"
b. Click Advanced > Environment Variables.
in the user variable->click new or edit then give variable name as CLASSPATH.and value as location of your .class file
eg.your class is in D' means give D:\
Add the location of classes� folder containing all your java classes in User Variables.
If there are already some entries in the CLASSPATH variable then you must add a semicolon and then add the new value . The new class path takes effect in each new command prompt window you open after setting the CLASSPATH variable.
thats all...
Vinoth-KRm