diff --git a/Customers/Invoices.aspx b/Customers/Invoices.aspx
index f34c189..a9764d3 100644
--- a/Customers/Invoices.aspx
+++ b/Customers/Invoices.aspx
@@ -90,13 +90,18 @@
                         <div style="height:0.936768149882904vh"></div>
                         <div class="col-12" id="cont4">
                             <div class="col-12" id="container2" style="margin-left:2px">
+                                <asp:Label ID="lbl_Kundennr" runat="server" Text="Kundennr"></asp:Label> 
+                                <asp:TextBox ID="txt_KundenNr" runat="server" Type="Number" CssClass="classTarget" requiered="true" AutoCompleteType="Search" OnTextChanged="txt_KundenNr_TextChanged"></asp:TextBox>
+                                <asp:RequiredFieldValidator ID="reqfield_txt_kundenNr" runat="server" ControlToValidate="txt_KundenNr" ErrorMessage="" Display="Dynamic" SetFocusOnError="true"></asp:RequiredFieldValidator>
                                 <asp:Label ID="lbl_von" runat="server" Text="Von:"></asp:Label>
                                   <%Dim erster = New Date(Now().Year, Now().Month, 1) %>
                                 <asp:TextBox ID="pickdate1" Type="Date" CssClass="classTarget" requiered="true" OnTextChanged="pickdate1_TextChanged" minDate="<%=erster %>" runat="server"></asp:TextBox>
+                                <asp:RequiredFieldValidator ControlToValidate="pickdate1" Display="Dynamic" ID="valreq_pickdate1" runat="server" ErrorMessage=""></asp:RequiredFieldValidator>
                                 <asp:CustomValidator runat="server" ID="valDateRange_1" ControlToValidate="pickdate1" Display="Dynamic" OnServerValidate="valDateRange_1_ServerValidate" ErrorMessage="" SetFocusOnError="true" ValidationGroup="Datevalid"></asp:CustomValidator>
                                 <asp:Label ID="lbl_bis" runat="server" Text="Bis:"></asp:Label>
                                 <%Dim jetzt = DateTime.Now.Date %>
                                 <asp:TextBox ID="pickdate2" Type="Date" CssClass="classTarget" OnTextChanged="pickdate2_TextChanged" required="true" runat="server" minDate="<%=jetzt %>"></asp:TextBox>
+                                <asp:RequiredFieldValidator ControlToValidate="pickdate2" Display="Dynamic" ID="valreq_pickdate2" runat="server" ErrorMessage=""></asp:RequiredFieldValidator>
                                 <asp:CustomValidator runat="server" ID="valDateRange_2" ControlToValidate="pickdate2" Display="Dynamic" OnServerValidate="valDateRange_2_ServerValidate" ErrorMessage="" SetFocusOnError="true" ValidationGroup="Datevalid"></asp:CustomValidator>
                             </div>
                             <div id="Abstand"></div>
diff --git a/Customers/Invoices.aspx.vb b/Customers/Invoices.aspx.vb
index c7ea11a..bc28937 100644
--- a/Customers/Invoices.aspx.vb
+++ b/Customers/Invoices.aspx.vb
@@ -238,109 +238,148 @@ Partial Class Customers_Invoices
             MsgBox("Dieser Bereich ist nicht gestattet! Ein Fehler ist bei der Validierung der ID aufgetreten! Bitte erneut versuchen!", MsgBoxStyle.Information, "Error in User Area!")
         End Try
         dt = Nothing
-        If txt_Absender.Text IsNot "" Then
-            txt_Absender.ValidateRequestMode = UI.ValidateRequestMode.Enabled
-            Try
-                Absender = txt_Absender.Text
-            Catch ex As FormatException
+        reqfield_txt_kundenNr.Validate()
+        valreq_pickdate1.Validate()
+        valreq_pickdate2.Validate()
+        If reqfield_txt_kundenNr.IsValid AndAlso valreq_pickdate1.IsValid AndAlso valreq_pickdate2.IsValid Then
+            If txt_Absender.Text IsNot "" Then
+                regexval_txt_Absender.Enabled = True
+                regexval_txt_Absender.Validate()
+                txt_Absender.ValidateRequestMode = UI.ValidateRequestMode.Enabled
+                Try
+                    If regexval_txt_Absender.IsValid = True Then
+                        Absender = txt_Absender.Text
+                    Else
+                        Absender = String.Empty
+                    End If
+                Catch ex As FormatException
 
-            End Try
-        End If
-        If txt_Empfaenger.Text IsNot "" Then
-            txt_Empfaenger.ValidateRequestMode = UI.ValidateRequestMode.Enabled
-            Try
-                Empfaenger = txt_Empfaenger.Text
-            Catch ex As FormatException
+                End Try
+            End If
+            If txt_Empfaenger.Text IsNot "" Then
+                regexval_txt_Empfaenger.Enabled = True
+                regexval_txt_Empfaenger.Validate()
+                txt_Empfaenger.ValidateRequestMode = UI.ValidateRequestMode.Enabled
+                Try
+                    If regexval_txt_Empfaenger.IsValid = True Then
+                        Empfaenger = txt_Empfaenger.Text
+                    Else
+                        Empfaenger = String.Empty
+                    End If
+                Catch ex As FormatException
 
-            End Try
-        End If
-        If txt_KdNrAuftrag.Text IsNot "" Then
-            txt_KdNrAuftrag.ValidateRequestMode = UI.ValidateRequestMode.Enabled
-            Try
-                KDNAFNR = txt_KdNrAuftrag.Text
-            Catch ex As FormatException
+                End Try
+            End If
+            If txt_KdNrAuftrag.Text IsNot "" Then
+                regexval_txt_KdNrAuftrag.Enabled = True
+                regexval_txt_KdNrAuftrag.Validate()
+                txt_KdNrAuftrag.ValidateRequestMode = UI.ValidateRequestMode.Enabled
+                Try
+                    If regexval_txt_KdNrAuftrag.IsValid = True Then
+                        KDNAFNR = txt_KdNrAuftrag.Text
+                    Else
+                        KDNAFNR = String.Empty
+                    End If
+                Catch ex As FormatException
 
-            End Try
-        End If
-        If txt_LKWNr.Text IsNot "" Then
-            txt_LKWNr.ValidateRequestMode = UI.ValidateRequestMode.Enabled
-            Try
-                LKWNR = txt_LKWNr.Text
-            Catch ex As FormatException
+                End Try
+            End If
+            If txt_LKWNr.Text IsNot "" Then
+                regexval_txt_LKW.Enabled = True
+                regexval_txt_LKW.Validate()
+                txt_LKWNr.ValidateRequestMode = UI.ValidateRequestMode.Enabled
+                Try
+                    If regexval_txt_LKW.IsValid = True Then
+                        LKWNR = txt_LKWNr.Text
+                    Else
+                        LKWNR = String.Empty
+                    End If
+                Catch ex As FormatException
 
-            End Try
-        End If
-        If txt_ReNr.Text IsNot "" Then
-            txt_ReNr.ValidateRequestMode = UI.ValidateRequestMode.Enabled
-            Try
-                reNr = txt_ReNr.Text
-            Catch ex As FormatException
+                End Try
+            End If
+            If txt_ReNr.Text IsNot "" Then
+                regexval_txt_ReNr.Enabled = True
+                regexval_txt_ReNr.Validate()
+                txt_ReNr.ValidateRequestMode = UI.ValidateRequestMode.Enabled
+                Try
+                    If regexval_txt_ReNr.IsValid = True Then
+                        reNr = txt_ReNr.Text
+                    Else
+                        reNr = String.Empty
+                    End If
+                Catch ex As FormatException
 
-            End Try
-        End If
+                End Try
+            End If
 
-        If txt_Absender_M.Text IsNot "" Then
-            txt_Absender_M.ValidateRequestMode = UI.ValidateRequestMode.Enabled
-            Try
-                Absender = txt_Absender_M.Text
-            Catch ex As FormatException
+            If txt_Absender_M.Text IsNot "" Then
+                txt_Absender_M.ValidateRequestMode = UI.ValidateRequestMode.Enabled
+                Try
+                    Absender = txt_Absender_M.Text
+                Catch ex As FormatException
 
-            End Try
-        End If
-        If txt_Empfaenger_M.Text IsNot "" Then
-            txt_Empfaenger_M.ValidateRequestMode = UI.ValidateRequestMode.Enabled
-            Try
-                Empfaenger = txt_Empfaenger_M.Text
-            Catch ex As FormatException
+                End Try
+            End If
+            If txt_Empfaenger_M.Text IsNot "" Then
+                txt_Empfaenger_M.ValidateRequestMode = UI.ValidateRequestMode.Enabled
+                Try
+                    Empfaenger = txt_Empfaenger_M.Text
+                Catch ex As FormatException
 
-            End Try
-        End If
-        If txt_KdNrAuftrag_M.Text IsNot "" Then
-            txt_KdNrAuftrag_M.ValidateRequestMode = UI.ValidateRequestMode.Enabled
-            Try
-                KDNAFNR = txt_KdNrAuftrag_M.Text
-            Catch ex As FormatException
+                End Try
+            End If
+            If txt_KdNrAuftrag_M.Text IsNot "" Then
+                txt_KdNrAuftrag_M.ValidateRequestMode = UI.ValidateRequestMode.Enabled
+                Try
+                    KDNAFNR = txt_KdNrAuftrag_M.Text
+                Catch ex As FormatException
 
-            End Try
-        End If
-        If txt_LKWNr_M.Text IsNot "" Then
-            txt_LKWNr_M.ValidateRequestMode = UI.ValidateRequestMode.Enabled
-            Try
-                LKWNR = txt_LKWNr_M.Text
-            Catch ex As FormatException
+                End Try
+            End If
+            If txt_LKWNr_M.Text IsNot "" Then
+                txt_LKWNr_M.ValidateRequestMode = UI.ValidateRequestMode.Enabled
+                Try
+                    LKWNR = txt_LKWNr_M.Text
+                Catch ex As FormatException
 
-            End Try
-        End If
-        If txt_ReNr_M.Text IsNot "" Then
-            txt_ReNr_M.ValidateRequestMode = UI.ValidateRequestMode.Enabled
-            Try
-                reNr = txt_ReNr_M.Text
-            Catch ex As FormatException
+                End Try
+            End If
+            If txt_ReNr_M.Text IsNot "" Then
+                txt_ReNr_M.ValidateRequestMode = UI.ValidateRequestMode.Enabled
+                Try
+                    reNr = txt_ReNr_M.Text
+                Catch ex As FormatException
 
-            End Try
-        End If
-        pickdate1.ValidateRequestMode = UI.ValidateRequestMode.Enabled
-        pickdate2.ValidateRequestMode = UI.ValidateRequestMode.Enabled
-        If pickdate1.Text = Nothing Or pickdate2.Text = Nothing Then
-            Try
-                Dim erster = New Date(Now().Year, Now().Month, 1)
-                Dim ersterdat = erster.Day.ToString + "." + Now().Month.ToString + "." + Now().Year.ToString
-                ' MsgBox(ersterdat)
-                datevon = ersterdat
-                pickdate1.Text = erster.Day.ToString + "." + Now().Month.ToString + "." + Now().Year.ToString
-                datebis = Date.Parse(Now().Day.ToString + "." + Now().Month.ToString + "." + Now().Year.ToString).ToString
-                pickdate2.Text = Date.Parse(Now().Day.ToString + "." + Now().Month.ToString + "." + Now().Year.ToString).ToString
-            Catch ex As ValidationException When Date.ParseExact(pickdate1.Text, "dd.MM.yyyy", Nothing).Year < Date.ParseExact("2001", "yyyy", Nothing).Year And Date.ParseExact(pickdate2.Text, "dd.MM.yyyy", Nothing).Year > Date.ParseExact(Today, "dd.MM.yyyy", Nothing).Year
-                MsgBox("Die Zeitzonen sind nicht gültig!", MsgBoxStyle.Exclamation)
-            End Try
+                End Try
+            End If
+            pickdate1.ValidateRequestMode = UI.ValidateRequestMode.Enabled
+            pickdate2.ValidateRequestMode = UI.ValidateRequestMode.Enabled
+            If pickdate1.Text = Nothing Or pickdate2.Text = Nothing Then
+                Try
+                    Dim erster = New Date(Now().Year, Now().Month, 1)
+                    Dim ersterdat = erster.Day.ToString + "." + Now().Month.ToString + "." + Now().Year.ToString
+                    ' MsgBox(ersterdat)
+                    datevon = ersterdat
+                    pickdate1.Text = erster.Day.ToString + "." + Now().Month.ToString + "." + Now().Year.ToString
+                    datebis = Date.Parse(Now().Day.ToString + "." + Now().Month.ToString + "." + Now().Year.ToString).ToString
+                    pickdate2.Text = Date.Parse(Now().Day.ToString + "." + Now().Month.ToString + "." + Now().Year.ToString).ToString
+                Catch ex As ValidationException When Date.ParseExact(pickdate1.Text, "dd.MM.yyyy", Nothing).Year < Date.ParseExact("2001", "yyyy", Nothing).Year And Date.ParseExact(pickdate2.Text, "dd.MM.yyyy", Nothing).Year > Date.ParseExact(Today, "dd.MM.yyyy", Nothing).Year
+                    MsgBox("Die Zeitzonen sind nicht gültig!", MsgBoxStyle.Exclamation)
+                End Try
+            Else
+                Try
+                    datevon = Date.Parse(pickdate1.Text)
+                    datebis = Date.Parse(pickdate2.Text)
+                Catch ex As ValidationException When Date.ParseExact(pickdate1.Text, "dd.MM.yyyy", Nothing).Year < Date.ParseExact("2001", "yyyy", Nothing).Year And Date.ParseExact(pickdate2.Text, "dd.MM.yyyy", Nothing).Year > Date.ParseExact(Today, "dd.MM.yyyy", Nothing).Year
+                    MsgBox("Die Zeitzonen sind nicht gültig!", MsgBoxStyle.Exclamation)
+                End Try
+            End If
         Else
-            Try
-                datevon = Date.Parse(pickdate1.Text)
-                datebis = Date.Parse(pickdate2.Text)
-            Catch ex As ValidationException When Date.ParseExact(pickdate1.Text, "dd.MM.yyyy", Nothing).Year < Date.ParseExact("2001", "yyyy", Nothing).Year And Date.ParseExact(pickdate2.Text, "dd.MM.yyyy", Nothing).Year > Date.ParseExact(Today, "dd.MM.yyyy", Nothing).Year
-                MsgBox("Die Zeitzonen sind nicht gültig!", MsgBoxStyle.Exclamation)
-            End Try
         End If
+    End Sub
+
+    Protected Sub txt_KundenNr_TextChanged(sender As Object, e As EventArgs)
 
     End Sub
 End Class