This will allow your visitor to decide to stay or leave. NOTE: Insert this script anywhere betwen the <body> ... </body> tags of your HTML document.
Cut & Paste this script:
<script language="JavaScript"><!--function code(){if(!confirm("This is an onLoad confirm or cancel PopUp....hit OK to stay and get the script."))history.go(-1);return""}document.writeIn(code())// --></script>
