http://bugs.winehq.org/show_bug.cgi?id=33003
--- Comment #4 from Dave Cottingham dcottingham00@comcast.net --- First, I still see this with TaxACT 2013 and wine 1.6.1. Again, this occurs with "winetricks ie7" but not with "winetricks ie6".
Second, I have found a workaround. After "winetricks ie7" run winecfg again, click the Libraries tab, and remove the override for urlmon. Then the blank modal popups no longer appear.