The Site Policy Agreement window (that users must agree to when they first login to the site) appears blank in both IE6 and IE7, but displays fine in Firefox 2.
I tried using both an html file and a plain text file, but IE will not display either of them (but Firefox works fine).
I tried it using both the standard theme and the standardwhite theme and the results were the same.
I tried it from two different computers, one running WinXP Pro and the other running WinXP Home and the results were the same. I also tried it logging in with both an admin user and a normal student user and results were the same.
I have the site policy file located in mydomain.com/moodle/sitepolicy/sitepolicy.html . The Site Policy URL is obviously correct since it works in Firefox.