I had a similar problem to you on only one of my (several) machines - the error message being from memory something about being unable to unzip something during the install ? - all the others installations of 6.14 were fine.
The solution was not obvious as the problem was still there after uninstalling all of Java.
I finally resolved it by doing a manual delete of all Sun/Java odds and sods left in Documents and Settings (for each user) under Application Data. You do need to show Hidden Files if you do need to do this