I had to rebuild all of our office servers over the weekend (don't ask!) and after the rebuild we noticed a problem with saving changes to the server which the designers use for editing; when changing CSS files, after a few changes the server would stop reflecting those changes in the browser. So, say you change some CSS property, refresh the page...result...change isn't reflected in the browser. Well, I tried EVERYTHING to get this working (had the usual...'well it was working until recently'...which wasn't possible), tried changing IIS 6.0 HTTP headers to expire content immediately, changed the IE caching settings, the lot. Eventually, I did a google trawl and found the possible solution (he's still trying it) to this issue...a registry change to IIS 6.0 Kernel Mode caching...
The 'solution' is to add a DWORD key to HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\HTTP\Parameters called UriEnableCache with a value of 0. Apparently this change will disable Kernel Mode caching...hopefully solving this problem...all the registry settings are here