diff --git a/app/src/main/java/eu/faircode/netguard/ActivityMain.java b/app/src/main/java/eu/faircode/netguard/ActivityMain.java
index 15dac416..74ed1f01 100644
--- a/app/src/main/java/eu/faircode/netguard/ActivityMain.java
+++ b/app/src/main/java/eu/faircode/netguard/ActivityMain.java
@@ -25,6 +25,7 @@ import android.view.View;
 import android.widget.CompoundButton;
 import android.widget.Switch;
 import android.widget.TextView;
+import android.widget.Toast;
 
 import java.util.List;
 
@@ -58,13 +59,19 @@ public class ActivityMain extends AppCompatActivity implements SharedPreferences
             public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                 if (isChecked) {
                     Log.i(TAG, "Switch on");
-                    Intent intent = VpnService.prepare(ActivityMain.this);
-                    if (intent == null) {
+                    Intent prepare = VpnService.prepare(ActivityMain.this);
+                    if (prepare == null) {
                         Log.e(TAG, "Prepare done");
                         onActivityResult(REQUEST_VPN, RESULT_OK, null);
                     } else {
-                        Log.i(TAG, "Start intent=" + intent);
-                        startActivityForResult(intent, REQUEST_VPN);
+                        Log.i(TAG, "Start intent=" + prepare);
+                        try {
+                            startActivityForResult(prepare, REQUEST_VPN);
+                        } catch (Throwable ex) {
+                            Log.e(TAG, ex.toString() + "\n" + Log.getStackTraceString(ex));
+                            onActivityResult(REQUEST_VPN, RESULT_CANCELED, null);
+                            Toast.makeText(ActivityMain.this, ex.toString(), Toast.LENGTH_LONG).show();
+                        }
                     }
                 } else {
                     Log.i(TAG, "Switch off");
diff --git a/app/src/main/java/eu/faircode/netguard/BlackHoleService.java b/app/src/main/java/eu/faircode/netguard/BlackHoleService.java
index 20bcd51c..21ae51a4 100644
--- a/app/src/main/java/eu/faircode/netguard/BlackHoleService.java
+++ b/app/src/main/java/eu/faircode/netguard/BlackHoleService.java
@@ -12,6 +12,7 @@ import android.net.VpnService;
 import android.os.ParcelFileDescriptor;
 import android.preference.PreferenceManager;
 import android.util.Log;
+import android.widget.Toast;
 
 import java.io.IOException;
 
@@ -70,7 +71,8 @@ public class BlackHoleService extends VpnService {
                 Log.i(TAG, "Allowing " + rule.info.packageName);
                 try {
                     builder.addDisallowedApplication(rule.info.packageName);
-                } catch (PackageManager.NameNotFoundException ignored) {
+                } catch (PackageManager.NameNotFoundException ex) {
+                    Log.e(TAG, ex.toString() + "\n" + Log.getStackTraceString(ex));
                 }
             }
 
@@ -80,7 +82,18 @@ public class BlackHoleService extends VpnService {
         builder.setConfigureIntent(pi);
 
         // Start VPN service
-        vpn = builder.establish();
+        try {
+            vpn = builder.establish();
+        } catch (Throwable ex) {
+            Log.e(TAG, ex.toString() + "\n" + Log.getStackTraceString(ex));
+
+            // Disable firewall
+            SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
+            prefs.edit().putBoolean("enabled", false).apply();
+
+            // Feedback
+            Util.toast(ex.toString(), Toast.LENGTH_LONG, this);
+        }
     }
 
     private void vpnStop() {
@@ -88,7 +101,8 @@ public class BlackHoleService extends VpnService {
         try {
             vpn.close();
             vpn = null;
-        } catch (IOException ignored) {
+        } catch (IOException ex) {
+            Log.e(TAG, ex.toString() + "\n" + Log.getStackTraceString(ex));
         }
     }
 
diff --git a/app/src/main/java/eu/faircode/netguard/Util.java b/app/src/main/java/eu/faircode/netguard/Util.java
index 42765d5c..87c1e44b 100644
--- a/app/src/main/java/eu/faircode/netguard/Util.java
+++ b/app/src/main/java/eu/faircode/netguard/Util.java
@@ -7,7 +7,10 @@ import android.content.pm.PackageManager;
 import android.net.ConnectivityManager;
 import android.net.NetworkInfo;
 import android.os.Bundle;
+import android.os.Handler;
+import android.os.Looper;
 import android.util.Log;
+import android.widget.Toast;
 
 import java.util.Set;
 
@@ -28,6 +31,15 @@ public class Util {
 
     }
 
+    public static void toast(final String text, final int length, final Context context) {
+        new Handler(Looper.getMainLooper()).post(new Runnable() {
+            @Override
+            public void run() {
+                Toast.makeText(context, text, length).show();
+            }
+        });
+    }
+
     public static void logExtras(String tag, Intent intent) {
         logBundle(tag, intent.getExtras());
     }