Make sure that your machine clock is accurate both time/date and timezone-wise.
If you are running Internet Explorer 7 go to Tools/Internet Options/Advanced and click the Reset button. OK and exit, close and reopen IE7.
You will have to-enable all the browser add-ons.
If Internet Explorer 6 - go to Tools/Internet Options..
General tab: clear cookies, history and temporary files
Security tab: set all zones to default
Content tab: disable
Advanced tab: set to default. OK and exit.
See if that helps.
Also see this FAQ: http://service.mcafee.com/faqdocument.aspx?id=TS100431&lang=en_US&prior_tid=17&AnswerID=16777229&tur...