Edit specific line of text in a file

[johved]

I am trying to make the code edit the a line in a text file, but it ends up deleting all the text and add the line at the begging of the file.

       
        Dim FILE_NAME As String = "config.conf"
        Dim i As String
        Dim Text(90) As String


        Text(90) = "        Address = " & Chr(34) & KryptonTextBox1.Text & Chr(34) & ""

        Dim objWriter As New System.IO.StreamWriter(FILE_NAME)

        i = 90
        objWriter.WriteLine(Text(i))

        objWriter.Close()

the line i want to edit is line number 90



Thanks