We are having a few issues with group policy application through zdf policies. We have recently rolled out a new intranet which we would like to be everyones home page. However we currently have clients running IE6 and IE7 and each browser appears to be randomly ignoring the downloaded policy. For example a user on IE7 will one day have our new intranet as its start page and the next be directed to MSN.com instead. This occurs on both IE6 and IE7. We have policies workstation and user ones applied to all our users etc but have never had this issue before. I have posted this on the MS technet newsgroups and they suggested that I look at HKCU\Software\Microsoft\Internet Explorer\Main Start Page. On one workstation I looked at it did not have this value but creating it resolved the problem. However as this issue seems to occur randomly one day fine the next day msn.com I am assuming adding a value in the registry is probably not the real answer.

Does anybody have any idea why this is happening?