diff --git a/app/app.iml b/app/app.iml
index 4bffb70..f15f948 100644
--- a/app/app.iml
+++ b/app/app.iml
@@ -83,8 +83,8 @@
     </content>
     <orderEntry type="jdk" jdkName="Android API 21 Platform" jdkType="Android SDK" />
     <orderEntry type="sourceFolder" forTests="false" />
-    <orderEntry type="library" exported="" name="support-annotations-21.0.2" level="project" />
     <orderEntry type="library" exported="" name="support-v4-21.0.2" level="project" />
+    <orderEntry type="library" exported="" name="support-annotations-21.0.2" level="project" />
     <orderEntry type="library" exported="" name="appcompat-v7-21.0.2" level="project" />
   </component>
 </module>
diff --git a/app/src/main/java/me/datenknoten/tueroeffner/DerivBroadcastReceiver.java b/app/src/main/java/me/datenknoten/tueroeffner/DerivBroadcastReceiver.java
index 9123269..eca2843 100644
--- a/app/src/main/java/me/datenknoten/tueroeffner/DerivBroadcastReceiver.java
+++ b/app/src/main/java/me/datenknoten/tueroeffner/DerivBroadcastReceiver.java
@@ -21,24 +21,24 @@ public class DerivBroadcastReceiver extends BroadcastReceiver {
         final String action = intent.getAction();
         if (action.equals(WifiManager.NETWORK_STATE_CHANGED_ACTION)) {
             NetworkInfo nwInfo = intent.getParcelableExtra(WifiManager.EXTRA_NETWORK_INFO);
-            if (nwInfo.getExtraInfo().equals(MainActivity.networkSSID) && nwInfo.isConnected()) {
-                View rootView = ((Activity)context).getWindow().getDecorView().findViewById(android.R.id.content);
-                Button button = (Button) rootView.findViewById(R.id.button_buzzer);
-                button.setEnabled(true);
-                button = (Button) rootView.findViewById(R.id.button_door_unlock);
-                button.setEnabled(true);
-                button = (Button) rootView.findViewById(R.id.button_door_open);
-                button.setEnabled(true);
-                Toast.makeText(context, context.getString(R.string.wlan_connected), Toast.LENGTH_SHORT).show();
-            } else {
-                View rootView = ((Activity)context).getWindow().getDecorView().findViewById(android.R.id.content);
-                Button button = (Button) rootView.findViewById(R.id.button_buzzer);
-                button.setEnabled(false);
-                button = (Button) rootView.findViewById(R.id.button_door_unlock);
-                button.setEnabled(false);
-                button = (Button) rootView.findViewById(R.id.button_door_open);
-                button.setEnabled(false);
-            }
+                if (nwInfo.getExtraInfo() != null && nwInfo.getExtraInfo().equals(MainActivity.networkSSID) && nwInfo.isConnected()) {
+                    View rootView = ((Activity)context).getWindow().getDecorView().findViewById(android.R.id.content);
+                    Button button = (Button) rootView.findViewById(R.id.button2);
+                    button.setEnabled(true);
+                    button = (Button) rootView.findViewById(R.id.button3);
+                    button.setEnabled(true);
+                    button = (Button) rootView.findViewById(R.id.button);
+                    button.setEnabled(true);
+                    Toast.makeText(context, context.getString(R.string.wlan_connected), Toast.LENGTH_SHORT).show();
+                } else {
+                    View rootView = ((Activity)context).getWindow().getDecorView().findViewById(android.R.id.content);
+                    Button button = (Button) rootView.findViewById(R.id.button2);
+                    button.setEnabled(false);
+                    button = (Button) rootView.findViewById(R.id.button3);
+                    button.setEnabled(false);
+                    button = (Button) rootView.findViewById(R.id.button);
+                    button.setEnabled(false);
+                }
         }
     }
 }