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LinkClick.aspx
That's what's making life a little harder, because that's an additional redirect being thrown in the mix. You pass that thing a query string, which gets rolled into the Aptify querystring too.
So you end up with a query string parameter that contains a query string... breaks all but the most clever URL parsing routines
https://www.cda.org/member-login?returnurl=/LinkClick.aspx?fileticket=Ont4-l_m5Bg%3d&portalid=0
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