diff --git a/WebWindowComplex/TableComp.razor b/WebWindowComplex/TableComp.razor
index 45052a8..c9d5e7f 100644
--- a/WebWindowComplex/TableComp.razor
+++ b/WebWindowComplex/TableComp.razor
@@ -253,7 +253,7 @@
                                                                 {
 
                                                                     <div class="input-group mb-2 justify-content-center">
-                                                                        <button class="btn btn-outline-secondary btn-sm" @onclick="() => FrameWindow.AddSash()">Aggiungi window</button>
+                                                                        <button class="btn btn-outline-secondary btn-sm" @onclick="() => AddSashToFrame(FrameWindow)">Aggiungi window</button>
                                                                     </div>
                                                                 }
                                                             </div>
@@ -874,3 +874,10 @@
     }
 </div>
 
+@if (bError)
+{
+    <div class="alert alert-danger" role="alert">
+        Aggiunta finestra non possibile.
+    </div>
+}
+
diff --git a/WebWindowComplex/TableComp.razor.cs b/WebWindowComplex/TableComp.razor.cs
index df4bcbb..5e372b3 100644
--- a/WebWindowComplex/TableComp.razor.cs
+++ b/WebWindowComplex/TableComp.razor.cs
@@ -634,6 +634,7 @@ namespace WebWindowComplex
             currSplit = -1;
             currStep = CompileStep.Tree;
             editLock = false;
+            bError = false;
             await DoPreviewSvg();
         }
 
@@ -666,6 +667,8 @@ namespace WebWindowComplex
         {
             // reset editLock...
             editLock = false;
+            // reset variabile errori
+            bError = false;
         }
 
         /// <summary>
@@ -1119,6 +1122,12 @@ namespace WebWindowComplex
             currStep = CompileStep.Tree;
         }
 
+        private bool bError = false;
+        private void AddSashToFrame(Frame f)
+        {
+            bError = f.AddSash();
+        }
+
         /// <summary>
         /// Metodo per scambiare due aree di uno split
         /// </summary>
diff --git a/WebWindowComplex/WebWindowComplex.csproj b/WebWindowComplex/WebWindowComplex.csproj
index 5da86c0..c3ecb29 100644
--- a/WebWindowComplex/WebWindowComplex.csproj
+++ b/WebWindowComplex/WebWindowComplex.csproj
@@ -135,5 +135,6 @@
 
 
 
+
 
 
diff --git a/WebWindowComplex/Window.cs b/WebWindowComplex/Window.cs
index 473e3b5..d7bacff 100644
--- a/WebWindowComplex/Window.cs
+++ b/WebWindowComplex/Window.cs
@@ -265,40 +265,50 @@ namespace WebWindowComplex
             ParentWindow.OnUpdatePreview(ParentWindow.sSerialized());
         }
 
-        public void AddSash()
+        public bool AddSash()
         {
-            List<Area> ContentArea = new List<Area>();
+            // Salvo il parent
             Area ParentArea = AreaList[0].ParentArea;
-            // Salvo gli oggetti già presenti e li cancello da AreaList
-            ContentArea.Add(AreaList[0]);
-            AreaList.Remove(AreaList[0]);
-            // Aggiungo Area sash di default
+            // Creo area sash di default
             Sash SashArea = Sash.CreateSash(ParentArea);
             SashArea.SelFamilyHardware = Sash.s_FamilyHardwareList.First();
             SashArea.RefreshHardwareList();
-            SashArea.SetSelHardwareFromId(SashArea.HardwareList.First().Id);
-            // Aggiungo area
-            AreaList.Add(SashArea);
-            if (SashArea.nSashQty == 1)
+            if(SashArea.HardwareList.Count == 0)
             {
-                // Inserisco il riempimento precedente
-                AreaList[0].AreaList.Add(ContentArea[0]);
-                AreaList[0].AreaList[0].SetParentArea(AreaList[0]);
+                SashArea.Remove();
+                return true;
             }
             else
             {
-                // All'area Sash aggiunto uno Splitted per ogni anta
-                for (int i = 1; i < SashArea.nSashQty; i++)
+                SashArea.SetSelHardwareFromId(SashArea.HardwareList.First().Id);
+                // Salvo gli oggetti già presenti e li cancello da AreaList
+                List<Area> ContentArea = new List<Area>();
+                ContentArea.Add(AreaList[0]);
+                AreaList.Remove(AreaList[0]);
+                // Aggiungo area
+                AreaList.Add(SashArea);
+                if (SashArea.nSashQty == 1)
                 {
-                    AreaList[0].AreaList.Add(Splitted.CreateSplitted(SashArea));
+                    // Inserisco il riempimento precedente
+                    AreaList[0].AreaList.Add(ContentArea[0]);
+                    AreaList[0].AreaList[0].SetParentArea(AreaList[0]);
                 }
-                Fill fill2 = (Fill)ContentArea[0];
-                for (int i = 1; i < SashArea.nSashQty; i++)
+                else
                 {
-                    AreaList[0].AreaList[1].AreaList.Add(Fill.CreateFill(AreaList[0].AreaList[1], fill2.FillType));
+                    // All'area Sash aggiunto uno Splitted per ogni anta
+                    for (int i = 1; i < SashArea.nSashQty; i++)
+                    {
+                        AreaList[0].AreaList.Add(Splitted.CreateSplitted(SashArea));
+                    }
+                    Fill fill2 = (Fill)ContentArea[0];
+                    for (int i = 1; i < SashArea.nSashQty; i++)
+                    {
+                        AreaList[0].AreaList[1].AreaList.Add(Fill.CreateFill(AreaList[0].AreaList[1], fill2.FillType));
+                    }
                 }
+                ParentWindow.OnUpdatePreview(ParentWindow.sSerialized());
+                return false;
             }
-            ParentWindow.OnUpdatePreview(ParentWindow.sSerialized());
         }
 
         public void SwapAree()
diff --git a/WebWindowConfigurator/WebWindowConfigurator.csproj b/WebWindowConfigurator/WebWindowConfigurator.csproj
index 7df8926..833cdad 100644
--- a/WebWindowConfigurator/WebWindowConfigurator.csproj
+++ b/WebWindowConfigurator/WebWindowConfigurator.csproj
@@ -165,6 +165,9 @@
 
 
 
+
+
+