10:38:57 [SEVERE] Could not load 'plugins\JailLikeHell_v4.1.7.jar' in folder 'plugins' org.bukkit.plugin.InvalidPluginException: java.lang.UnsupportedClassVersionError : code/husky/JLH : Unsupported major.minor version 51.0 at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.j ava:150) at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager. java:305) at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager .java:230) at org.bukkit.craftbukkit.CraftServer.loadPlugins(CraftServer.java:207) at org.bukkit.craftbukkit.CraftServer.<init>(CraftServer.java:183) at net.minecraft.server.ServerConfigurationManager.<init>(ServerConfigur ationManager.java:53) at net.minecraft.server.MinecraftServer.init(MinecraftServer.java:156) at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:422) at net.minecraft.server.ThreadServerApplication.run(SourceFile:492) Caused by: java.lang.UnsupportedClassVersionError: code/husky/JLH : 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 org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader. java:41) at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader. java:29) at java.lang.ClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Unknown Source) at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.j ava:139) ... 8 more