All-day events not showing

I use Outlook 2000 SP-3. My all-day events stopped appearing at the top of the page in the "one day" view (current view = day/week/month with Autopreview.) But they were still there-- if I clicked on the line directly under the date, they would appear. I switched to the current view = day/week/month, and was able to see the all-day events again on a "one day view," until today, when they are again hidden unless I click on the line directly under the date. What do I need to do so that I can always see my all-day events in the "one-day" screen? I appreciate any help.

--Jasper