Open IE, go to the advanced section under Tools/options. Then look at the Java settings. What do you have listed there and what is checked? If you have both MS JVM and Sun, are both checked? If you only have Sun is it checked? Also, if both are present and checked, uncheck sun and then try it.
another thing to try,
go to %userprofile%
then delete the .java folder there. Go to Application Data, delete the Sun folder.
Then try it again.