Originally Posted by
CrossBow
Not sure which you are using, but I would first Uninstall ALL JAVA that you have through control panel first.
Then only install one version of Java in your system. As was stated, version 6 is required, but always best to go with the latest version. So I would install Java 8 but try the 32-bit version first. Again, only have just the one Java version installed initially. Then see if you can click on the xgmrombuilder.jar file just like running an application. That is how I use it. If that still fails, then uninstall java and try a different version, switching between the 32bit and 64bit versions. Also make sure you are not only installing the .JRE but also the .JDK. This way you not only have the standard runtime files that most people have already, but also have the development files installed just to be sure. I usually install the .JDK and then the .JRE.
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