This is usually an issue in the below scenarios:
(1)When you downloaded 32 bit eclipse on 64 bit machine or
(2)When you are using 64 bit java on 32 bit machine
Below are some of the things that I tried and worked out.
For Eclipse Juno:
SET PATH for 64 bit jdk.
SET PATH=C:\Program Files\Java\jdk1.6.0_31\bin
SET EXE4J_JAVA_HOME=C:\Program Files\Java\jdk1.6.0_31
SET JAVA_HOME=C:\Program Files\Java\jdk1.6.0_31
This will help you to start eclipse
You can also try eclipse.exe clean in case of windows.
By default you should have the below settings:
EXE4J_JAVA_HOME=C:\Program Files (x86)\Java\jdk1.7.0_10
Path=C:\Program Files (x86)\Java\jdk1.7.0_10\bin
JAVA_HOME=C:\Program Files (x86)\Java\jdk1.7.0_10
Whenever any java 32 bit issue is seen ,point java home to 32 bit machine.
Another finding that I have observed is setting -vm argument in case of eclipse.ini