@Magma: Could you try to add

   <meta http-equiv="pragma" content="no-cache">

to the header of your template? May do the job in IE unless the size of the page is not too large. The workaround from Micro$oft’s KB #222064 looks weird. Not sure whether it is valid to add another head after the body…

I'm using the default theme, where do I put this code please?

themes - default - ?