Hello there!

I've been able to solve the first half of the problem. I am exporting a multiline listbox entry (with 14 columns, I'll expand that later) by DoubleClick from one UserForm to another -

Private Sub ListBox3_DblClick(ByVal Cancel As MSForms.ReturnBoolean)
    Dim MyData As DataObject
    Dim i As Long
    Dim strCopiedText As String
    Dim dVal As Double

    Set MyData = New DataObject
    With Me.ListBox3
        For i = 1 To .ListCount
            If .Selected(i - 1) Then
                strCopiedText = strCopiedText & _
                                .List(i - 1, 1) & vbTab & _
                               .List(i - 1, 0) & vbTab & _
                               .List(i - 1, 1) & vbTab & _
                               .List(i - 1, 2) & vbTab & _
                               .List(i - 1, 3) & vbTab & _
                               .List(i - 1, 4) & vbTab & _
                               .List(i - 1, 5) & vbTab & _
                               .List(i - 1, 6) & vbTab & _
                               .List(i - 1, 7) & vbTab & _
                               .List(i - 1, 8) & vbTab & _
                               .List(i - 1, 9) & vbCrLf
                               
                               
                               
            End If
        Next i
        If Len(strCopiedText) > 0 Then
            MyData.Clear
            MyData.SetText strCopiedText
            MyData.PutInClipboard
        End If
    End With

UserForm4!TextBox1.Text = strCopiedText
UserForm4.Show
End Sub
In UserForm4 I got a Textbox (Textbox1) and tried saving the changes to the Textbox to my Excel Worksheet (Tabelle2) -

Private Sub CommandButton2_Click()
   Dim ws As Worksheet, ws1 As Worksheet
    Dim rng As Range
    Dim lastRow As Long
    Dim Ar As Variant
    Dim Tb As Range

    Set ws = Sheets("Tabelle2")


    lastRow = ws.Cells.Find(What:="*", After:=ws.Range("A2"), _
              Lookat:=xlPart, LookIn:=xlFormulas, _
              SearchOrder:=xlByRows, SearchDirection:=xlPrevious, _
              MatchCase:=False).Row

    Set rng = ws.Range("A2:N" & lastRow)

    Set ws1 = Sheets.Add

    With rng
        ws.AutoFilterMode = False
        .AutoFilter Field:=1, Criteria1:=TextBox1.Text
        .SpecialCells(xlCellTypeVisible).Replace(ws1.Range("A1"),Textbox1.Text)
        ws.AutoFilterMode = False
        lastRow = ws1.Cells.Find(What:="*", After:=ws1.Range("A2"), _
                  Lookat:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows, _
                  SearchDirection:=xlPrevious, MatchCase:=False).Row
                  

        Ar = ws1.Range("A2:N" & lastRow)

        Application.DisplayAlerts = False
        ws1.Delete
        Application.DisplayAlerts = True
    End With
End Sub
However that does not work at all.

        .SpecialCells(xlCellTypeVisible).Replace(ws1.Range("A1"),Textbox1.Text)
I was thinking I could search for the entry I'm trying to replace and then replace it with Textbox1.Text . Excel tells me I got a syntax error.

Sorry, I'm completely lost. I just cannot get Excel/Vba to determine the original entry (my database is quite big with about 14 columns of up to 400 entries each) and then replace the whole string with my Textbox text.

Thanks again for any input!