Hi, Scott Sorry to bother you again. I've runned more tests, and found that for *.html files connection is kept alive, while for cgi program, it always close connection. Even when I just change my cgi program name with .html extension, connection becomes alive though the displayed content is in a mess. I've tried a simple html file and a cgi program which just produce the same html file. The *.html file works fine(I mean connection keeps alive) while not the cgi program. Also I found that in the HTTP GET header by Inetnet Explorer there is one: If-None-Match: some random value here, and in the reply by IIS there is a ETag: same value as in If-None-Match. Are such headers defined in HTTP 1.0 or 1.1? Related to connection problem? Thanks in advance! Xuemei