Hi, On the osm forum someone reported this error with OSM combiner (http://www.openfietsmap.nl/news/osmcombiner) (mkgmap r.3654) http://forum.openstreetmap.org/viewtopic.php?id=30632 What does Unsupported major.minor version 51.0 mean? ------------------ Unfortunately the new OSM Combiner 1.8 did not solve the problem for me. I dowloaded a fresh set of osm_generic_tiles.zip files for the Netherlands, Belgium and France and tried to combine them with OSM combiner 1.8 but consistently get an error message (see below). All steps up to "Start" work, the final step fails and gives the error message. I use MacOS 10.11.3 with the latest Java installed and allocated 5gb of memory to Java, disk space is plenty. What am I doing wrong? Thank you! --- Error message: Exception in thread "main" java.lang.UnsupportedClassVersionError: uk/me/parabola/mkgmap/main/Main : Unsupported major.minor version 51.0 at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClassCond(ClassLoader.java:637) at java.lang.ClassLoader.defineClass(ClassLoader.java:621) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141) at java.net.URLClassLoader.defineClass(URLClassLoader.java:283) at java.net.URLClassLoader.access$000(URLClassLoader.java:58) at java.net.URLClassLoader$1.run(URLClassLoader.java:197) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:190) at java.lang.ClassLoader.loadClass(ClassLoader.java:306) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301) at java.lang.ClassLoader.loadClass(ClassLoader.java:247)