how to delete text

Sub WriteKonfFile()
   Dim objFSO, cTxtFile
   Set objFSO = CreateObject("Scripting.FileSystemObject")
   Set cTxtFile = objFSO.CreateTextFile(App.Path & "\conf.txt", True)
   
    cTxtFile.WriteLine ("server " & cmbServer.Text)
    cTxtFile.WriteLine ("proxy 192.168.1.1")
    cTxtFile.WriteLine ("proxy-option " & txtProxy.Text)
 
 
   cTxtFile.Close
End Sub