Do I need to reinstall Java?

[Janeice DelVecchio]

Apparently, something is pretty messed up. I'm getting the following message, that I have never seen before, and I'm getting it on known-good and new applications. Is there a fix for this, or do I have to reinstall?

C:\Users\Janeice\Documents>javac HelloWorld.java

C:\Users\Janeice\Documents>java HelloWorld
Exception in thread "main" java.lang.NoClassDefFoundError: HelloWorld
Caused by: java.lang.ClassNotFoundException: HelloWorld
        at java.net.URLClassLoader$1.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClassInternal(Unknown Source)
Could not find the main class: HelloWorld.  Program will exit.    

Here's the code... I made it because I was getting this error on something else that WAS working before.

class HelloWorld {
	public static void main(String[] args) {
		System.out.println("Hello World");
	}
}    

[Dinah Gans]

Was there a change to your environmental variables? That's one idea.

Are you trying to save to a flash drive? I was having similar error messages using a flash drive where it wouldn't compile after I edited a .java file on my school computer.

I was able to fix it without reinstalling, I believe I just copied it to the C: drive, compiled, and copied back to my flash drive.

Hope this helps or if not someone else can help.

[Janeice DelVecchio]

Dinah Gans wrote:Was there a change to your environmental variables? That's one idea.

You know I checked and there was nothing changed, I ran a Java update and rebooted and it worked fine.

Weird.

Thanks!

[Henry Wong]

Having a classpath set incorrectly can cause this issue too.

Henry