IE setting for checking for new pages

Ah, for some reason I have 2 users in the company whose IE browsers when they open them up in the morning will display the old pages from the last time they looked at the page and not the current page. Ex: they open it up today, but it will display the page for Friday, when they refresh it – it updates the page. I have deleted cookies, temp files, temp internet files, deleted all off-line content, cleared history, selected in IE settings to automatically check for newer versions of pages, reformated the harddrive (just kidding!)… Anyways, where is that setting kept – I am really sick of looking for it? IE 5.5, Win98.