Error

17:05:57 [SEVERE] java.io.FileNotFoundException: plugins\AutoMessage\config.yml
(The requested operation cannot be performed on a file with a user-mapped sectio
n open)
17:05:57 [SEVERE]       at java.io.FileOutputStream.open(Native Method)
17:05:57 [SEVERE]       at java.io.FileOutputStream.<init>(Unknown Source)
17:05:57 [SEVERE]       at java.io.FileOutputStream.<init>(Unknown Source)
17:05:57 [SEVERE]       at java.io.PrintWriter.<init>(Unknown Source)
17:05:57 [SEVERE]       at com.JnaniDev.AutoMessage.AutoMessage.removeHeader(Aut
oMessage.java:155)
17:05:57 [SEVERE]       at com.JnaniDev.AutoMessage.AutoMessage.save(AutoMessage
.java:170)
17:05:57 [SEVERE]       at com.JnaniDev.AutoMessage.AutoMessage.load(AutoMessage
.java:237)
17:05:57 [SEVERE]       at com.JnaniDev.AutoMessage.AMCommandExecutor.reload(AMC
ommandExecutor.java:294)
17:05:57 [SEVERE]       at com.JnaniDev.AutoMessage.AMCommandExecutor.onCommand(
AMCommandExecutor.java:23)
17:05:57 [SEVERE]       at org.bukkit.command.PluginCommand.execute(PluginComman
d.java:40)
17:05:57 [SEVERE]       at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCo
mmandMap.java:166)
17:05:57 [SEVERE]       at org.bukkit.craftbukkit.CraftServer.dispatchCommand(Cr
aftServer.java:479)
17:05:57 [SEVERE]       at net.minecraft.server.NetServerHandler.handleCommand(N
etServerHandler.java:821)
17:05:57 [SEVERE]       at net.minecraft.server.NetServerHandler.chat(NetServerH
andler.java:781)
17:05:57 [SEVERE]       at net.minecraft.server.NetServerHandler.a(NetServerHand
ler.java:764)
17:05:57 [SEVERE]       at net.minecraft.server.Packet3Chat.handle(Packet3Chat.j
ava:34)
17:05:57 [SEVERE]       at net.minecraft.server.NetworkManager.b(NetworkManager.
java:229)
17:05:57 [SEVERE]       at net.minecraft.server.NetServerHandler.a(NetServerHand
ler.java:113)
17:05:57 [SEVERE]       at net.minecraft.server.NetworkListenThread.a(NetworkLis
tenThread.java:78)
17:05:57 [SEVERE]       at net.minecraft.server.MinecraftServer.w(MinecraftServe
r.java:558)
17:05:57 [SEVERE]       at net.minecraft.server.MinecraftServer.run(MinecraftSer
ver.java:450)
17:05:57 [SEVERE]       at net.minecraft.server.ThreadServerApplication.run(Sour
ceFile:492)