I have an aspx.cs page with the following code:

hypPopup.Attributes.Add("onclick",
                        "window.open('Popup.aspx',
                        '',
                        'height=650,
                         width=800,
                         location=no,
                         toolbar=no, 
                         status=no, 
                         scrollbars=yes, 
                         resizable=yes');
                         return false"
                         );

When I click the hypPopup link, the window pops up which is fine, but if I close it and refresh the page, the popup keeps popping up. I have to leave the page and come back for it to stop popping up on every refresh. Is this behavior by default or is there a fix to it?

hypPopup.Attributes.Add is done in the Page_Load