diff --git a/indra/newview/quickprefs.cpp b/indra/newview/quickprefs.cpp
index 39a640f6c4..785dae3366 100644
--- a/indra/newview/quickprefs.cpp
+++ b/indra/newview/quickprefs.cpp
@@ -1575,6 +1575,13 @@ void FloaterQuickPrefs::onValuesChanged()
 	// if we changed the control's variable, rebuild the user interface
 	if (!new_control_name.empty() && old_control_name != new_control_name)
 	{
+		if (mControlsList.find(new_control_name) != mControlsList.end())
+		{
+			LL_WARNS() << "Selected control has already been added" << LL_ENDL;
+			LLNotificationsUtil::add("QuickPrefsDuplicateControl");
+			return;
+		}
+
 		// remember the old control parameters so we can restore them later
 		ControlEntry old_parameters = mControlsList[mSelectedControl];
 		// disable selection so the border doesn't cause a crash
diff --git a/indra/newview/skins/default/xui/de/notifications.xml b/indra/newview/skins/default/xui/de/notifications.xml
index 6d03b0728d..9f533e8a68 100644
--- a/indra/newview/skins/default/xui/de/notifications.xml
+++ b/indra/newview/skins/default/xui/de/notifications.xml
@@ -5068,6 +5068,10 @@ Diese Aktion setzt die Schnelleinstellungen direkt auf die Standardkonfiguration
 Diese Aktion kann nicht rückgängig gemacht werden.
 		<usetemplate ignoretext="Bestätigen, wenn Schnelleinstellungen zurückgesetzt werden sollen" name="okcancelignore" notext="Abbrechen" yestext="OK"/>
 	</notification>
+	<notification name="QuickPrefsDuplicateControl">
+		Einstellung wurde bereits hinzugefügt. Bitte eine andere Einstellung wählen.
+		<usetemplate name="okbutton" yestext="OK"/>
+	</notification>
 
 	<notification name="ExportFinished">
 Export nach [FILENAME] beendet.
diff --git a/indra/newview/skins/default/xui/en/notifications.xml b/indra/newview/skins/default/xui/en/notifications.xml
index 560e6ff60c..2aa68c123d 100644
--- a/indra/newview/skins/default/xui/en/notifications.xml
+++ b/indra/newview/skins/default/xui/en/notifications.xml
@@ -12543,6 +12543,17 @@ You cannot undo this action.
      notext="Cancel"
      yestext="OK"/>
     </notification>
+
+    <notification
+     icon="alertmodal.tga"
+     name="QuickPrefsDuplicateControl"
+     type="alertmodal">
+     <tag>fail</tag>
+Setting has already been added. Please select a different one.
+    <usetemplate
+     name="okbutton"
+     yestext="OK"/>
+    </notification>
     
     <notification
      icon="alertmodal.tga"