How would I prevent the browser from opening the pop up window that was displayed from the previous page when the user clicks the back button?

 I hope that made sense but I'll explain it in point form below:
There are three pages: Page1, Page2, Page3
User loads Page1 and clicks a link to load Page2 in a new window using JavaScript (i.e. window.open(...)). The User can close Page2 anytime they wish-- but we'll assume the user does so before step 2.
User now clicks a link on Page1 to load Page3.
User is now on Page3 and clicks the back button on their browser.
Page1 is displayed in the browser but Page2 is displayed again in a pop up window.
So, I'm wondering if there is a way to prevent Page2 from popping up again. I am using ASP.NET and VB.NET.
 
Thanks in Advance
Shabbir
 
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