Strange Problem with getting Content from YML File

Hi,
I have a little big problem with my Plugin.
I wanna get a string from a .yml file but i just get an internal error ingame.
The Console give me such a output:

Code:

org.bukkit.command.CommandException: Unhandled exception executing command 'quest' in plugin PermissionsQuest v1.1
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:42)
    at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:166)
    at org.bukkit.craftbukkit.CraftServer.dispatchCommand(CraftServer.java:473)
    at net.minecraft.server.NetServerHandler.handleCommand(NetServerHandler.java:821)
    at net.minecraft.server.NetServerHandler.chat(NetServerHandler.java:781)
    at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:764)
    at net.minecraft.server.Packet3Chat.handle(Packet3Chat.java:34)
    at net.minecraft.server.NetworkManager.b(NetworkManager.java:229)
    at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:113)
    at net.minecraft.server.NetworkListenThread.a(NetworkListenThread.java:78)
    at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:551)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:449)
    at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
Caused by: java.lang.NullPointerException
    at me.MolaynoxX.PermissionsQuest.PermissionsQuest.onCommand(PermissionsQuest.java:245)
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:40)
    ... 12 more

Here is my Source: http://pastie.org/4013206

The command works on my homeserver without any error but it doesnt work on my public server. (Same Java Version, Same Bukkit Version, Same YML Files)

If i check the content of the yml file with .isString it returns true but if i wanna get the string there is just an error.

Thanks for all people, which help me and sorry for my bad english.

 

Well, you gave us an error that points to me.MolaynoxX.PermissionsQuest.PermissionsQuest but you gave us me.MolaynoxX.ProspercityQuests.ProspercityQuest. That doesn't fit at all.

 

Oh crap i have the old Version (with another name) and the new one on my public Server.
I test some things and look if it works now.

Edit: Ok now it's working, thanks for helping me to fix my stupidness