IE & Outlook display problems

I have a PC running XP Pro, IE 6.0 & MS Outlook for email. Recently Outlook has chosen to not display the text in the body of the email. If I hit reply, I can see the text fine. The added signitures display fine, but anything in the body of the email will not display. Also Internet Explorer has decided not to display all of the webpages I go to. Some are OK, but there are some that only part of the page is displayed. I have tried re-installng Media Flash Player, but it had no effect. When I log onto this PC as a different user, everyhting works fine. Any ideas as to what is causing this?