After applying SP15 Roles Tab doesn't work

Hi,

I just finished an EP 6.0 6.40 installation and applied SP15, and I am facing a problem. when I click on roles I get an IE error which is : Inernet explorer cannot open the site http://hostname:50000/irj/portal. I checked the other postings and people say they resolved this problem with SP15. Any idea?

Thanks,

Serkan