SpigotCore_Main/src/de/steamwar/core/events/PlayerJoinedEvent.java

@@ -12,7 +12,7 @@ public class PlayerJoinedEvent implements Listener{
 
 	@EventHandler
 	private void onJoin(PlayerJoinEvent event) {
-		Player player = event.getPlayer(); 
+		Player player = event.getPlayer();
 		SteamwarUser user = SteamwarUser.get(player.getUniqueId());
 
 		switch(user.getUserGroup()){

SpigotCore_Main/src/de/steamwar/inventory/SWItem.java

@@ -30,11 +30,15 @@ public class SWItem {
     }
 
     public static Material getMaterial(String material){
-        switch(Core.getVersion()){
-            case 14:
-                return SWItem_v14.getMaterial(material);
-            default:
-                return SWItem_v12.getMaterial(material);
+        try{
+            switch(Core.getVersion()){
+                case 14:
+                    return SWItem_v14.getMaterial(material);
+                default:
+                    return SWItem_v12.getMaterial(material);
+            }
+        }catch(IllegalArgumentException e){
+            return Material.STONE;
         }
     }
 

SpigotCore_Main/src/de/steamwar/sql/SteamwarUser.java

@@ -32,7 +32,7 @@ public class SteamwarUser {
 			id = rs.getInt("id");
 			uuid = java.util.UUID.fromString(rs.getString("UUID"));
 			userName = rs.getString("UserName");
-			userGroup = de.steamwar.sql.UserGroup.valueOf(rs.getString("UserGroup"));
+			userGroup = UserGroup.valueOf(rs.getString("UserGroup"));
 			team = rs.getInt("Team");
 
 			byUUID.put(uuid, this);