When you refer to "Page" do you mean Browser Windows?
Is "Page1" the parent browser window to "Page2" (the child browser window)?
You cannot do this using ASP.NET code (by this I mean your VB.NET code). Your VB.NET code runs on the server and it has absolutely no control over what happens with the browser.
You are going to have to use JavaScript for this purpose.
What you need to do (if you're talking about browser windows) is implement a JavaScript method in "Page1" (the parent window) that will postback to the server so that the page can be refreshed.
In "Page2" (the child window) you will have to implement a method that executes when the browser window closes. The only way (that I know of) to check when the window is being closed this is to use the JavaScript
onbeforeunload event (this event is not supported by Opera at this time).
So when the onbeforeunload event happens in the child browser, you have to call the JavaScript method that posts back to the server in the parent window. You can use the
window.opener to accomplish this.
I've moved your question to the JavaScript forum.
-Frinny