[05:01:13] [Server thread/ERROR]: Could not load 'plugins/Lootbox v1.4.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.UnsupportedClassVersionError: me/TheOatBaron/Bukkit/Lootbox : Unsupported major.minor version 52.0
	at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:131) ~[craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:328) ~[craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:251) [craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at org.bukkit.craftbukkit.v1_7_R3.CraftServer.loadPlugins(CraftServer.java:355) [craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at org.bukkit.craftbukkit.v1_7_R3.CraftServer.<init>(CraftServer.java:317) [craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.PlayerList.<init>(PlayerList.java:68) [craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.DedicatedPlayerList.<init>(SourceFile:14) [craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.DedicatedServer.init(DedicatedServer.java:126) [craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.MinecraftServer.run(MinecraftServer.java:436) [craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.ThreadServerApplication.run(SourceFile:628) [craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
Caused by: java.lang.UnsupportedClassVersionError: me/TheOatBaron/Bukkit/Lootbox : Unsupported major.minor version 52.0
	at java.lang.ClassLoader.defineClass1(Native Method) ~[?:1.7.0_67]
	at java.lang.ClassLoader.defineClass(ClassLoader.java:800) ~[?:1.7.0_67]
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) ~[?:1.7.0_67]
	at java.net.URLClassLoader.defineClass(URLClassLoader.java:449) ~[?:1.7.0_67]
	at java.net.URLClassLoader.access$100(URLClassLoader.java:71) ~[?:1.7.0_67]
	at java.net.URLClassLoader$1.run(URLClassLoader.java:361) ~[?:1.7.0_67]
	at java.net.URLClassLoader$1.run(URLClassLoader.java:355) ~[?:1.7.0_67]
	at java.security.AccessController.doPrivileged(Native Method) ~[?:1.7.0_67]
	at java.net.URLClassLoader.findClass(URLClassLoader.java:354) ~[?:1.7.0_67]
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:77) ~[craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:62) ~[craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:425) ~[?:1.7.0_67]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ~[?:1.7.0_67]
	at java.lang.Class.forName0(Native Method) ~[?:1.7.0_67]
	at java.lang.Class.forName(Class.java:270) ~[?:1.7.0_67]
	at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:40) ~[craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:127) ~[craftbukkit-1.7.10-gbk.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	... 9 more