diff --git a/src/mibew/js/source/users/model_views/visitor.js b/src/mibew/js/source/users/model_views/visitor.js
index db09c3f7..928a0993 100644
--- a/src/mibew/js/source/users/model_views/visitor.js
+++ b/src/mibew/js/source/users/model_views/visitor.js
@@ -76,14 +76,22 @@
                     var visitorId = this.model.id;
                     var page = Mibew.Objects.Models.page;
 
-                    // Open invite window
-                    Mibew.Popup.open(
-                        page.get('inviteLink')
-                            + '?visitor='
-                            + visitorId,
-                        'ImCenter' + visitorId,
-                        Mibew.Utils.buildWindowParams(page.get('inviteWindowParams'))
-                    );
+                    // Check whether operator could actually chat
+                    // (see libs/operator.php, has_online_operators function for details)
+                    if (page.get('operatorCouldNotInvite')) {
+                        Mibew.Utils.alert(Mibew.Localization.trans('Unable to invite user: groups are enabled, and you don\'t belong to any of them.'));
+                    }
+                    else {
+
+                        // Open invite window
+                        Mibew.Popup.open(
+                            page.get('inviteLink')
+                                + '?visitor='
+                                + visitorId,
+                            'ImCenter' + visitorId,
+                            Mibew.Utils.buildWindowParams(page.get('inviteWindowParams'))
+                        );
+                    }
                 }
             },
 
diff --git a/src/mibew/libs/classes/Mibew/Controller/UsersController.php b/src/mibew/libs/classes/Mibew/Controller/UsersController.php
index ff47c8b2..5bf30008 100644
--- a/src/mibew/libs/classes/Mibew/Controller/UsersController.php
+++ b/src/mibew/libs/classes/Mibew/Controller/UsersController.php
@@ -124,6 +124,8 @@ class UsersController extends AbstractController
                     'banLink' => $request->getBaseUrl() . '/operator/ban',
                     'inviteLink' => $request->getBaseUrl() . '/operator/invite',
 
+                    'operatorCouldNotInvite' => (Settings::get('enablegroups') == 1) && !count(get_operator_group_ids($operator['operatorid'])),
+
                     'chatWindowParams' => $chat_style_config['chat']['window'],
                     'trackedUserWindowParams' => $page_style_config['tracked']['user_window'],
                     'trackedVisitorWindowParams' => $page_style_config['tracked']['visitor_window'],