Preserve QueryString parameter in Sharepoint iFrame
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the problem: when sending out marketing emails we should track on the website whether user came by a link from an email. The site is hosted in SharePoint 2003 environment and our *.aspx page is in an iFrame. How can I pass QueryString parameter from SharePoint URL to the iFrame URL? 

In other words, if user comes by URL:

    http://mainsite.com/default.aspx?email=1

then my iFrame should point to:

`http:/iframesite.com/page.aspx?email=1`, otherwise to `http:/iframesite.com/page.aspx`


I don't have development control over the CMS, only editorial one. Thanks in advance.