HI I am using IE.au3 to automate a web application. at one point of the script, a strange behaviour occurs as follow: I use the following code to wait that an object exists: Do ; waiting that an object is generated (by javascript or ajax) Local $oPseudoButton = _IEGetObjById($oFrame,"button6_ManageDtls") ConsoleWrite(".") ; to see that script is going on Sleep(250) ; give some time to build Until IsObj($oPseudoButton) ConsoleWrite(@CRLF&"Button exist"&@CRLF) ; OK button