Where are these image cached and how can I force them to be refreshed?

[chopper99]

If I call up a page in my browser, it appears ok. If I change the html, then when I refresh the page in the browser, I get the altered page as I expect. If, however, I change a jpeg or a flash file – but without changing the name of the jpeg or flash (i.e. the html is unchanged), then the page doesn’t refresh properly in the browser, the old picture or flash is still displayed. No problem, I think - it must be cached on the PC. But that doesn’t seem to be the case. I deleted everything in the cache (including offline files), refreshed the page – and watched as the old picture got loaded back into the cache.

So it seems to be being cached in the server somewhere. This seems to be confirmed by looking in the IIS Manager on the server. If I look at the jpeg via the IIS manager, and choose "open in browser" it shows me the old picture. Change the name of the file to something else, refresh the view in the IIS Manager, and the new – correct – picture is displayed. Rename the file back again and I see the old picture again.

At some point the page is updated, but sometimes this can be several hours after the file changed.

So where on the server is the information being cached, and how can I force this cache to be flushed?

There was some discussion on a similar theme to this in an earlier thread, but nothing I have found so far has helped.