I have a user who cannot get to our site from IE8. They can with ie7, ie9, firefox, opera, safari. However, when they go to our secure site from our parent site (both are using HTTPS and are using single sign on with CA's Siteminder), if IE8 is the browser, they get an 'Internet explorer cannot display this page'. The 'More information' selector shows no error other than IE could not connect to this site. This affects all machines at their business that use IE8.
I've ruled out a communication issue because other browsers can see it. I have loaded up IE8 and it "works fine on my machine". Our settings in 'Internet Options > Advanced' match. There is no autoconfig script configured. Our site is in trusted sites and security for trusted is low.
Any ideas?