diff --git a/Common/Forms/ModelessForm.cs b/Common/Forms/ModelessForm.cs
index 6af087f10..ec477ee60 100644
--- a/Common/Forms/ModelessForm.cs
+++ b/Common/Forms/ModelessForm.cs
@@ -1,4 +1,7 @@
-using System;
+///
+/// Copyright (c) 2021-2023 Sensus Slovensko a.s.
+///
+using System;
 using System.Drawing;
 using System.Windows.Forms;
 
@@ -53,20 +56,20 @@ namespace Common.Forms
         public event EventHandler<MessageEventArgs> UpdateMessageHandler;
         void OnUpdateMessage(object sender, MessageEventArgs args)
         {
-            if (args.Message != null) label1.Text = args.Message;
+            if (args != null && args.Message != null) label1.Text = args.Message;
         }
 
 
         /// <summary>
         /// Called from the state machine when an operation forces a modeless dialog close.
         /// </summary>
-        public static void CloseForm()
+        public void CloseForm()
         {
             if (CloseFormHandler == null) return;
             try { CloseFormHandler(null, null); }
             catch (Exception) { }
         }
-        static public event EventHandler<EventArgs> CloseFormHandler;
+        public event EventHandler<EventArgs> CloseFormHandler;
         void OnCloseForm(object sender, EventArgs args)
         {
             DialogResult = DialogResult.Cancel;