Private Sub WriteTextToFile(ByVal FilePath As String, _
        ByVal Inhalt As String, _
        Optional ByVal Anhängen As Boolean = False)
 
        Dim _PathInfo As New FileInfo(FilePath)
        Try
            If Not _PathInfo.Directory.Exists Then _PathInfo.Directory.Create()
            Dim _SW As New StreamWriter(_PathInfo.FullName, Anhängen)
            _SW.AutoFlush = True
            _SW.Write(Inhalt)
            _SW.Close()
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
    End Sub

WriteTextToFile("C:\Path\To\My\File.txt", "Blablabla ... ", True)