i am going to try to explain what i want  
 $fr = FileRead(@ScriptDir & "\lastip.txt")
   $xp = 0
   While 1
	If $xp < 11 Then
	 $xp = $xp + 1
	 $f1 = FileReadLine($config, $xp)
	 $text = FileRead($f1, FileGetSize($f1))
	 $text = StringReplace($text, "Your IP" Or $fr, @IPAddress1)
	 FileDelete($f1)
	 FileWrite($f1, $text)
	 Sleep(200)
	 MsgBox(0, "Edited", "Line : " & $xp)
	EndIf
wend
 
in the lastip.txt there is an ip adress 
but in the file that a am replacing the string i dont know