Vic, I'm surprissed that Java 7 isn't backward compatible with Java 6. It looks like the problem may be in the manifest, and could be an Ant problem. However, there are others on this list who are more knowledgeable. I know that some people are using your 32-bit version of BrailleBlaster 1.3.0. Hopefully someone knows of an easy fix. Questions for others. BrailleBlaster was written using Java 1.6, because that was what was available. Does Java 1.7 have features that would be useful to us? Would switching to Java 1.7 cause more compatibility problems? Thanks, John On Sat, Mar 10, 2012 at 07:30:18PM -0500, Vic Beckley wrote: > John, > > I am compiling Braille Blaster and the DLLs using version 7 of the Java JDK. > I am having no problems with running what I compile on the same Java > version. I just gave a copy of my 32-bit version to a friend to try out. He > is running Java version 6. It won't run. He gets the below error. I also > tried it on my laptop, which also has Java 6, and got the same error. > > Exception in thread "main" java.lang.UnsupportedClassVersionError: > org/brailleblaster/Main : Unsupported major.minor version 51.0 > at java.lang.ClassLoader.defineClass1(Native Method) > at java.lang.ClassLoader.defineClassCond(Unknown Source) > at java.lang.ClassLoader.defineClass(Unknown Source) > at java.security.SecureClassLoader.defineClass(Unknown Source) > at java.net.URLClassLoader.defineClass(Unknown Source) > at java.net.URLClassLoader.access$000(Unknown Source) > at java.net.URLClassLoader$1.run(Unknown Source) > at java.security.AccessController.doPrivileged(Native Method) > at java.net.URLClassLoader.findClass(Unknown Source) > at java.lang.ClassLoader.loadClass(Unknown Source) > at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) > at java.lang.ClassLoader.loadClass(Unknown Source) > Could not find the main class: org.brailleblaster.Main. Program will exit. > > Any ideas what would cause this? Will I have to compile with Java 6? If so, > will it run on Java 7? > > Is anyone running my 32-bit Windows release of Braille Blaster 1.3.0 > successfully? If so, what Java version do you have? > > > Best regards from Ohio, U.S.A., > > Vic > E-mail: vic.beckley3@xxxxxxxxx > > > -- John J. Boyer; President, Chief Software Developer Abilitiessoft, Inc. http://www.abilitiessoft.com Madison, Wisconsin USA Developing software for people with disabilities