var WindowName="Popup";
var HomeUrl="http://www.columnbangkok.com/index.asp";

function CheckWindow(){
    if((window.name==null) || (window.name=="")){
        //location.href=HomeUrl;
    }
}

function OpenWeb() {
var left=screen.width+10;
var width=500; var height=400;
var position_x = (screen.width-width)/2;
var position_y = (screen.height-height)/2;
    strFeatures = "toolbar=0, scrollbars=0, location=0, statusbar=0, menubar=0, resizable=0, width="+width+", height="+height+", left="+left+", top=0";
    pathihan = window.open("popup.html", WindowName, strFeatures);
    pathihan.moveTo(position_x, position_y);
    pathihan.focus();

}

if (top.location != HomeUrl) {
    CheckWindow();
}