IE 9 does not display Welcome Page for 11.0.3, 11.0.4 or 11.0.6

Hi folks,

I'm using IE9 (I've tried with and without add-ons, safe mode, 32-bit etc.).

I've tried this with Cognos 11.0.3, 11.0.4 and 11.0.6, all configured to use SSO. They all work in Firefox and Chrome, but return a pop-up for the login followed b...