diff --git a/src/main/java/com/Acrobot/ChestShop/Commands/AddAccessor.java b/src/main/java/com/Acrobot/ChestShop/Commands/AddAccessor.java
index 8d39f3f8f..d2431f862 100644
--- a/src/main/java/com/Acrobot/ChestShop/Commands/AddAccessor.java
+++ b/src/main/java/com/Acrobot/ChestShop/Commands/AddAccessor.java
@@ -2,7 +2,8 @@
 
 import static com.Acrobot.ChestShop.Permission.ADMIN;
 
-import org.bukkit.Bukkit;
+import java.util.UUID;
+
 import org.bukkit.block.Block;
 import org.bukkit.block.Sign;
 import org.bukkit.command.Command;
@@ -14,6 +15,7 @@
 import com.Acrobot.ChestShop.Permission;
 import com.Acrobot.ChestShop.Configuration.Messages;
 import com.Acrobot.ChestShop.Signs.ChestShopSign;
+import com.Acrobot.ChestShop.UUIDs.NameManager;
 
 /**
  * @author Acrobot
@@ -53,12 +55,17 @@ public boolean onCommand(CommandSender sender, Command command, String label, St
         }
 
         String playerName = args[0];
-        Player newAccessor = Bukkit.getPlayer(playerName);
+        UUID newAccessor = NameManager.getUUIDFor(playerName);
         if (newAccessor == null) {
             sender.sendMessage(Messages.prefix(Messages.UNKNOWN_PLAYER));
             return true;
         }
 
+        if (ChestShopSign.isAccessor(newAccessor, sign)) {
+            sender.sendMessage(Messages.prefix(Messages.ACCESSOR_ALREADY_ADDED));
+            return true;
+        }
+
         ChestShopSign.addAccessor(newAccessor, sign);
         sender.sendMessage(Messages.prefix(Messages.NEW_ACCESSOR_ADDED));
         return true;
diff --git a/src/main/java/com/Acrobot/ChestShop/Commands/RemoveAccessor.java b/src/main/java/com/Acrobot/ChestShop/Commands/RemoveAccessor.java
index 2a5788731..0188b7a65 100644
--- a/src/main/java/com/Acrobot/ChestShop/Commands/RemoveAccessor.java
+++ b/src/main/java/com/Acrobot/ChestShop/Commands/RemoveAccessor.java
@@ -2,7 +2,8 @@
 
 import static com.Acrobot.ChestShop.Permission.ADMIN;
 
-import org.bukkit.Bukkit;
+import java.util.UUID;
+
 import org.bukkit.block.Block;
 import org.bukkit.block.Sign;
 import org.bukkit.command.Command;
@@ -14,6 +15,7 @@
 import com.Acrobot.ChestShop.Permission;
 import com.Acrobot.ChestShop.Configuration.Messages;
 import com.Acrobot.ChestShop.Signs.ChestShopSign;
+import com.Acrobot.ChestShop.UUIDs.NameManager;
 
 /**
  * @author Acrobot
@@ -53,12 +55,17 @@ public boolean onCommand(CommandSender sender, Command command, String label, St
         }
 
         String playerName = args[0];
-        Player accessorToRemove = Bukkit.getPlayer(playerName);
+        UUID accessorToRemove = NameManager.getUUIDFor(playerName);
         if (accessorToRemove == null) {
             sender.sendMessage(Messages.prefix(Messages.UNKNOWN_PLAYER));
             return true;
         }
 
+        if (!ChestShopSign.isAccessor(accessorToRemove, sign)) {
+            sender.sendMessage(Messages.prefix(Messages.ACCESSOR_NOT_ADDED));
+            return true;
+        }
+
         ChestShopSign.removeAccessor(accessorToRemove, sign);
         sender.sendMessage(Messages.prefix(Messages.ACCESSOR_REMOVED));
         return true;
diff --git a/src/main/java/com/Acrobot/ChestShop/Configuration/Messages.java b/src/main/java/com/Acrobot/ChestShop/Configuration/Messages.java
index 8e2f8e5cb..d963f4dca 100644
--- a/src/main/java/com/Acrobot/ChestShop/Configuration/Messages.java
+++ b/src/main/java/com/Acrobot/ChestShop/Configuration/Messages.java
@@ -90,7 +90,9 @@ public class Messages {
     @PrecededBySpace
     public static final String UNKNOWN_PLAYER = "Player not found.";
     public static final String NEW_ACCESSOR_ADDED = "New accessor added.";
-    public static final String ACCESSOR_REMOVED = "New accessor removed.";
+    public static final String ACCESSOR_ALREADY_ADDED = "Accessor already added.";
+    public static final String ACCESSOR_REMOVED = "Accessor removed.";
+    public static final String ACCESSOR_NOT_ADDED = "Player isn't a accessor.";
 
     public static String prefix(String message) {
         return PREFIX + message;
diff --git a/src/main/java/com/Acrobot/ChestShop/Signs/ChestShopSign.java b/src/main/java/com/Acrobot/ChestShop/Signs/ChestShopSign.java
index 2aa35c70b..0e8e698aa 100644
--- a/src/main/java/com/Acrobot/ChestShop/Signs/ChestShopSign.java
+++ b/src/main/java/com/Acrobot/ChestShop/Signs/ChestShopSign.java
@@ -168,15 +168,20 @@ public static Collection<String> getAccessors(Sign sign) {
         return new HashSet<>(Arrays.asList(split));
     }
 
-    public static void addAccessor(OfflinePlayer player, Sign sign) {
+    public static void addAccessor(UUID player, Sign sign) {
         Collection<String> accessors = getAccessors(sign);
-        accessors.add(player.getUniqueId().toString());
+        accessors.add(player.toString());
         saveAccessors(accessors, sign);
     }
 
-    public static void removeAccessor(OfflinePlayer player, Sign sign) {
+    public static boolean isAccessor(UUID player, Sign sign) {
         Collection<String> accessors = getAccessors(sign);
-        accessors.remove(player.getUniqueId().toString());
+        return accessors.contains(player.toString());
+    }
+
+    public static void removeAccessor(UUID player, Sign sign) {
+        Collection<String> accessors = getAccessors(sign);
+        accessors.remove(player.toString());
         saveAccessors(accessors, sign);
     }