first thing is, you can not close the page which is parent, cause you have open a child page from client,
Your JavaScript code can only close a window without confirmation that was previously opened by window.open(). This is an intentional security precaution because a script running on a webpage does not own the window, and by closing it discards the browsing history in that window.
The workaround is to either have a "welcome page" or otherwise some sort of page that pops up the window you want to close with window.open in the first place, or to tell your users to modify their browser security settings to allow your application to close their windows.
Thanks
Koolprasd2003
Editor, DotNetSpider MVM
Microsoft MVP 2014 [ASP.NET/IIS]