After downloaded Groovy 1.0 and setup the environment, the execution of groovy command shows the following:
ERROR: JAVA_HOME is set to an invalid directory: c:\java\jdk1.6.0
Please set the JAVA_HOME variable in your environment to match the location of your Java installation.
Nonetheless the JDK is installed correctly:
The executable file (as in the usual JDK) java.exe is present.
JAVA is working fine in the station.