If you have IE6 sp1 please look at this URL: http://www.jmbsoft.com/software/arphp/demo/accounts.php theres gzip encoding. Hit submit, you.ll get error message, then hit back button. IE wont refresh old page, nothing will change. I got the same on my server, seems that is because url doesn.t change, but if disable the compression all works fine. Is that an IE bug?