Close Aspx Page That Is Redirect From Handler?

In my application I try to close opened window using javascript function.

function Close_Window() {
var myWin = window.open('', '_parent', '');
myWin.close();
}

this function is used in 3 aspx pages. That page will open from mail means my application is used for sending Mail. In that such as normal newsletter there will be three footer links like UnSubscribe,Forward A Friend,Change E-Mail address. So on click of close button for above these three pages I had written that code. The page will be opened from "ashx" file. And I try to close it using Javascript. So close button is working when I direct click on the above three links.

But by right clicking on that I open it in new window or new tab close button is not working. So how can I close aspx page using javascript or in code behind. My purpose is page should be close any how by javascript or by code behind. I am opening that page using ashx handler.