When i do /help it says unable to perform command even if im op
"[00:35:25] [Server thread/ERROR]: Couldn't process command: '?'
java.lang.IllegalArgumentException: Comparison method violates its general contract!
at java.util.ComparableTimSort.mergeHi(ComparableTimSort.java:835) ~[?:1.7.0_79]
at java.util.ComparableTimSort.mergeAt(ComparableTimSort.java:453) ~[?:1.7.0_79]
at java.util.ComparableTimSort.mergeForceCollapse(ComparableTimSort.java:392) ~[?:1.7.0_79]
at java.util.ComparableTimSort.sort(ComparableTimSort.java:191) ~[?:1.7.0_79]
at java.util.ComparableTimSort.sort(ComparableTimSort.java:146) ~[?:1.7.0_79]
at java.util.Arrays.sort(Arrays.java:472) ~[?:1.7.0_79]
at java.util.Collections.sort(Collections.java:155) ~[?:1.7.0_79]
at net.minecraft.command.CommandHelp.func_71534_d(SourceFile:84) ~[au.class:?]
at net.minecraft.command.CommandHelp.func_71515_b(SourceFile:38) ~[au.class:?]
at net.minecraft.command.CommandHandler.func_71556_a(CommandHandler.java:94) [z.class:?]
at net.minecraft.server.dedicated.DedicatedServer.func_71333_ah(DedicatedServer.java:370) [lt.class:?]
at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:335) [lt.class:?]
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:547) [MinecraftServer.class:?]
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:427) [MinecraftServer.class:?]
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685) [li.class:?]"
this is what it says. it is really annoying because i cannot access some mods like veinminer and such i hope you can fix this thank you..
