Exception error, Need Help!

Question

Need help!
Why my java program work well under C:\, but can't under D:\Java today? It worked well even yesterday. I had tried the "Hello World", it can not work under D:\Java either.
when I enter the "java d:\java\Hello" order(after javac of cause), those displays are here:
Exception in thread "main" java.lang.NoClassDefFoundError: d:\java\Hello
Caused by: java.lang.ClassNotFoundException:d:\java\Hello
at java.net.URLClassLoader$1.run<URLClassLoader.java:200>
at java.security.AccessController.doPrivileged<Native Method>
at java.net.URLClassLoader.findClass<URLClassLoader.java:188>
at java.lang.ClassLoader.loadClass<ClassLoader.java:306>
at sun.misc.Launcher$AppClassLoader.loadClass<Launcher.java:276>
at java.lang.ClassLoader.loadClass<ClassLoader.java:251>
at java.lang.ClassLoader.loadClassInternal<ClassLoader.java:319>
The Hello.java has no problem,and it worked well even yesterday!
I just don't know what had happened.
Someone who can help me please reply or email at [email protected]
Thank you!

Answer 1

The simple "Hello World" can work under Editplus, but can't under DOS.
The error appears as the same. I don't know what I should do, could you tell me please?
Thank you!First test whether environment variables had been set properlyor not
To test :-
1) Open cmd
2) type java
3) If it runs that means you have set it properly
Then go to your program directory i.e d:\java\
and type
javac Hello.java //to compile it and then
java Hello //To run it