diff --git a/res/values/strings.xml b/res/values/strings.xml
index c005ade..94e74a4 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -50,6 +50,7 @@
     <string name="check_for_updates_summary">Tap to check for updates</string>
     <string name="notification_settings_title">Notification settings</string>
     <string name="notification_settings_summary">Modify notification channel settings</string>
+    <string name="alert_pending_reboot">An update was previously downloaded and is ready to install, so it is not possible to download another update. Please reboot to install the pending update.</string>
     <string name="use_security_preview_channel_title">Receive security preview releases</string>
     <string name="use_security_preview_channel_summary_on">Use alternate release channels receiving security patches still under an embargo for source code and details</string>
     <string name="use_security_preview_channel_summary_off">Don\'t use alternate release channels receiving security patches still under an embargo for source code and details</string>
diff --git a/src/app/seamlessupdate/client/Settings.java b/src/app/seamlessupdate/client/Settings.java
index fb4af67..0e6937f 100644
--- a/src/app/seamlessupdate/client/Settings.java
+++ b/src/app/seamlessupdate/client/Settings.java
@@ -9,6 +9,7 @@
 import android.os.UserManager;
 import android.util.Log;
 import android.view.MenuItem;
+import android.app.AlertDialog;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
@@ -104,6 +105,13 @@ public static class SettingsFragment extends PreferenceFragmentCompat
             implements SharedPreferences.OnSharedPreferenceChangeListener {
         private static String TAG = "SettingsFragment";
 
+        private void showAlertDialogForPendingReboot(final Context context) {
+            new AlertDialog.Builder(context)
+                .setTitle(android.R.string.dialog_alert_title)
+                .setMessage(R.string.alert_pending_reboot)
+                .show();
+        }
+
         @Override
         public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
             getPreferenceManager().setStorageDeviceProtected();
@@ -121,6 +129,8 @@ public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
                     intent.putExtra(Service.INTENT_EXTRA_IS_USER_INITIATED, true);
                     intent.putExtra(Service.INTENT_EXTRA_NETWORK, network);
                     context.startForegroundService(intent);
+                } else {
+                    showAlertDialogForPendingReboot(context);
                 }
                 return true;
             });