Could not find or load main class

Question

I have Windows 7, installed jdk1.7.0 and its supporting jre7.
My problem is compilation part works perfectly, but while running the Java program I get this error saying:

Answer 1

First, put your file *.class (e.g Hello.class) into 1 folder (e.g C:\java). Then you try command and type cd /d C:\java. Now you can type "java Hello" !