[16:35:49] [Server thread/ERROR]: Error occurred while enabling Kesky v1.0 (Is it up to date?)
java.lang.NoClassDefFoundError: net/minecraft/server/v1_11_R1/Packet
	at kesky.Main.Main.updateFile(Main.java:45) ~[?:?]
	at kesky.Main.Main.onEnable(Main.java:17) ~[?:?]
	at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:264) ~[spigot.jar:git-Spigot-99c2a37-3819f8d]
	at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:337) [spigot.jar:git-Spigot-99c2a37-3819f8d]
	at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:402) [spigot.jar:git-Spigot-99c2a37-3819f8d]
	at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugin(CraftServer.java:378) [spigot.jar:git-Spigot-99c2a37-3819f8d]
	at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugins(CraftServer.java:327) [spigot.jar:git-Spigot-99c2a37-3819f8d]
	at net.minecraft.server.v1_12_R1.MinecraftServer.t(MinecraftServer.java:421) [spigot.jar:git-Spigot-99c2a37-3819f8d]
	at net.minecraft.server.v1_12_R1.MinecraftServer.l(MinecraftServer.java:382) [spigot.jar:git-Spigot-99c2a37-3819f8d]
	at net.minecraft.server.v1_12_R1.MinecraftServer.a(MinecraftServer.java:337) [spigot.jar:git-Spigot-99c2a37-3819f8d]
	at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:272) [spigot.jar:git-Spigot-99c2a37-3819f8d]
	at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:544) [spigot.jar:git-Spigot-99c2a37-3819f8d]
	at java.lang.Thread.run(Thread.java:748) [?:1.8.0_151]
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_11_R1.Packet
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:91) ~[spigot.jar:git-Spigot-99c2a37-3819f8d]
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:86) ~[spigot.jar:git-Spigot-99c2a37-3819f8d]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_151]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_151]
	... 13 more