Not having IE5 to hand at the moment I'm having to make a guess based on Netscape's options. In Netscape you can set your cache options to determine how often Netscape compares the cached copy of a page to the online version: Every time; once per session or never. If there's a similar setting in IE5 (I'll check tonight if you haven't replied by then) and either of the last two are selected then that would explain your problem.