BUNGEECORD NOT WORKING

It starts up all good, but when i try to connect to it i get
21:37:00 [SEVERE] Aug 21, 2016 9:37:00 PM io.netty.util.concurrent.SingleThreadEventExecutor runAllTasks
WARNING: A task raised an exception.
java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast to java.util.Collection
at net.md_5.bungee.conf.YamlConfig.getPermissions(YamlConfig.java:301)
at net.md_5.bungee.UserConnection.addGroups(UserConnection.java:486)
at...

BUNGEECORD NOT WORKING