For some reason the cache-control settings in "Host Settings" is being overridden. I have it set to "public" in DNN but these are the headers when accessing the site. You can see in the header that it shows "private".
Anyone know what can cause this?

HTTP/1.1 200 OK
Date: Thu, 22 Jan 2009 15:00:37 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
X-AspNet-Version: 2.0.50727
Set-Cookie: .ASPXANONYMOUS=57YSATSzyQEkAAAAYTY4MTgzYmItM2JhZC00NzJjLWFjMjAtZjNkYmE2NzAyN2U10; expires=Thu, 02-Apr-2009 01:40:29 GMT; path=/; HttpOnly
Set-Cookie: language=en-US; path=/; HttpOnly
Cache-Control: private
Content-Type: text/html; charset=utf-8
Content-Length: 259924
 

please take a look at it with http fiddler, you're likely to see different results e.g. the full headers will show that there is a "If-Modified-Since: Sun, 05 Jun 2005 03:13:00 GMT" value in the body, which matches the value in the header "Last-Modified: Sun, 05 Jun 2005 03:13:00 GMT", so the file doesn't get downloaded

GET /Portals/_default/Skins/DNN-Minimal/images/header-left.gif HTTP/1.1
Accept: */*
Referer: http://www.dotnetnuke.com/Community/Forums/tabid/795/forumid/-1/threadid/283097/scope/posts/Default.aspx
Accept-Language: en-gb
UA-CPU: x86
Accept-Encoding: gzip, deflate
If-Modified-Since: Sun, 05 Jun 2005 03:13:00 GMT
If-None-Match: "086617a7c69c51:220b"
User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.0.04506; InfoPath.2; OfficeLiveConnector.1.3; OfficeLivePatch.0.0; .NET CLR 3.5.21022)
Connection: Keep-Alive
Host: www.dotnetnuke.com
Pragma: no-cache


HTTP/1.1 200 OK
Cache-Control: max-age=86400
Content-Length: 758
Content-Type: image/gif
Last-Modified: Sun, 05 Jun 2005 03:13:00 GMT
Accept-Ranges: bytes
ETag: "086617a7c69c51:103d"
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Date: Thu, 29 Jan 2009 22:59:57 GMT