[16:20:13] [Server thread/WARN]: Failed to handle packet for /x.x.x.x:53915
java.lang.NullPointerException
        at net.minecraft.network.NetHandlerPlayServer.func_147346_a(NetHandlerPlayServer.java:926) ~[nh.class:?]
        at net.minecraft.network.play.client.C08PacketPlayerBlockPlacement.func_148833_a(SourceFile:60) ~[jo.class:?]
        at net.minecraft.network.play.client.C08PacketPlayerBlockPlacement.func_148833_a(SourceFile:9) ~[jo.class:?]
        at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:244) ~[ej.class:?]
        at net.minecraft.network.NetworkSystem.func_151269_c(NetworkSystem.java:173) [nc.class:?]
        at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:980) [MinecraftServer.class:?]
        at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:430) [lt.class:?]
        at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:798) [MinecraftServer.class:?]
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:658) [MinecraftServer.class:?]
        at java.lang.Thread.run(Thread.java:745) [?:1.7.0_79]
[16:20:13] [Server thread/INFO]: SwiftnessXVI lost connection: Internal server error