Bukkit

What steps will reproduce the problem?
1. Load the Plugins
2. Try to kill a player with the default skin
3. Check console for the error

What is the expected output? What do you see instead?
Expected output is getting a default player head with no error in console. Instead, there was an error in console.

What version of the product are you using? Latest.

Do you have an error log of what happened?

[15:37:17] [Server thread/WARN]: javax.imageio.IIOException: Can't get input stream from URL!
[15:37:17] [Server thread/WARN]:     at javax.imageio.ImageIO.read(ImageIO.java:1395)
[15:37:17] [Server thread/WARN]:     at me.AstramG.MoreMobHeads.MoreMobHeads.getImage(MoreMobHeads.java:159)
[15:37:17] [Server thread/WARN]:     at me.AstramG.MoreMobHeads.MoreMobHeads.playerDeath(MoreMobHeads.java:244)
[15:37:17] [Server thread/WARN]:     at sun.reflect.GeneratedMethodAccessor530.invoke(Unknown Source)
[15:37:17] [Server thread/WARN]:     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
[15:37:17] [Server thread/WARN]:     at java.lang.reflect.Method.invoke(Method.java:606)
[15:37:17] [Server thread/WARN]:     at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:292)
[15:37:17] [Server thread/WARN]:     at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
[15:37:17] [Server thread/WARN]:     at org.bukkit.plugin.TimedRegisteredListener.callEvent(TimedRegisteredListener.java:47)
[15:37:17] [Server thread/WARN]:     at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502)
[15:37:17] [Server thread/WARN]:     at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487)
[15:37:17] [Server thread/WARN]:     at org.bukkit.craftbukkit.v1_7_R2.event.CraftEventFactory.callPlayerDeathEvent(CraftEventFactory.java:366)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityPlayer.die(EntityPlayer.java:389)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityLiving.damageEntity(EntityLiving.java:739)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityHuman.damageEntity(EntityHuman.java:751)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityPlayer.damageEntity(EntityPlayer.java:468)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityMonster.n(EntityMonster.java:99)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityZombie.n(EntityZombie.java:224)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.PathfinderGoalMeleeAttack.e(PathfinderGoalMeleeAttack.java:100)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.PathfinderGoalSelector.a(PathfinderGoalSelector.java:108)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityInsentient.bm(EntityInsentient.java:433)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityLiving.e(EntityLiving.java:1448)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityInsentient.e(EntityInsentient.java:306)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityMonster.e(EntityMonster.java:20)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityZombie.e(EntityZombie.java:158)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityLiving.h(EntityLiving.java:1311)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityInsentient.h(EntityInsentient.java:150)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityMonster.h(EntityMonster.java:24)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.EntityZombie.h(EntityZombie.java:220)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.World.entityJoinedWorld(World.java:1486)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.World.playerJoinedWorld(World.java:1462)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.World.tickEntities(World.java:1329)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.WorldServer.tickEntities(WorldServer.java:515)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.MinecraftServer.v(MinecraftServer.java:678)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.DedicatedServer.v(DedicatedServer.java:273)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.MinecraftServer.u(MinecraftServer.java:568)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.MinecraftServer.run(MinecraftServer.java:474)
[15:37:17] [Server thread/WARN]:     at net.minecraft.server.v1_7_R2.ThreadServerApplication.run(SourceFile:618)
[15:37:17] [Server thread/WARN]: Caused by: java.io.IOException: Server returned HTTP response code: 403 for URL: http://s3.amazonaws.com/MinecraftSkins/Frostwolf137.png
[15:37:17] [Server thread/WARN]:     at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1626)
[15:37:17] [Server thread/WARN]:     at java.net.URL.openStream(URL.java:1037)
[15:37:17] [Server thread/WARN]:     at javax.imageio.ImageIO.read(ImageIO.java:1393)
[15:37:17] [Server thread/WARN]:     ... 37 more

By going to the url provided in the error, I could see it was denied. Then I cross referenced that with the player, and saw he had no skin.