ShowModalDialog pop up opens onclick of the browser back button

Hi,
I have an application made by using asp.net,C#.In that application there is a page having gridview displaying results.The grid view has a template column containing hyperlink. On click of the hyperlink there is modal popup opened using Javascript. The modal popup is closed successfully by closing it.Now I redirect to some other page for some operations. Now staying on the same page when I click the browser back button the modal popup is opened.The same scenario is observed in case the page is refreshed.I have opened the application using IE7 browser. Can you please help me to get solution for stopping the modalpopup to open.
Any help is appreciated in advance.


Thanks,
Santosh



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