Hi, i hope somebody can explain this to me , becaus i can?t explain this behavior. We are using squid as an reverse proxy in version 3.1.4. when i open a website in firefox the first time in the squid access.log i can see that there is nothing cached , an he is geting the content from the backend. Now it?s cached in squid and also in the browsercache. Then the second visite, in the proxy log file i can see a TCP_REFRESH_UNMODIFIED/304 and the request is send to the back-end. But why, the proxy has the file in it?s cache, why is the request passed thru to the backend. As far as i tested it this is onely happening with firefox and crome, when i do the same with opera an ie the log says : TCP_IMS_HIT/304 and the request in not passed to the back-end. Is there anything I can do to avoid that the request that do a TCP_REFRESH_UNMODIFIED/304 are send to the back ends ?? Thx for the help.