Ok, I think the problem may be that Mozilla just does not handle proxy authentication: This is a session with regular netscape 4.75 loading a simple file I put on my old student account. Note, where it says "session complete", that comes from my program, to indicate that the connection was closed.: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% GET http://www.cslab.vt.edu/~rostewa2/ HTTP/1.0 If-Modified-Since: Mon, 23 Oct 2000 22:42:44 GMT; length=14 Proxy-Connection: Keep-Alive User-Agent: Mozilla/4.75 [en] (X11; U; Linux 2.2.16-22 i686) Pragma: no-cache Host: www.cslab.vt.edu Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, image/png, */* Accept-Encoding: gzip Accept-Language: en Accept-Charset: iso-8859-1,*,utf-8 HTTP/1.1 407 Proxy authentication required Proxy-Authenticate: NTLM Proxy-Authenticate: Basic realm="192.168.11.5" Content-Length: 503 Content-Type: text/html Error 407

HTTP Error 407

407 Proxy Authentication Required

You must authenticate with a proxy server before this request can be serviced. Please log on to your proxy server, and then try again.

Please contact the Web server's administrator if this problem persists.

session complete ########################################### The session's not complete. At this point netscape prompts me for a name and password. After I enter those in, the session continues. ########################################### GET http://www.cslab.vt.edu/~rostewa2/ HTTP/1.0 Proxy-Connection: Keep-Alive User-Agent: Mozilla/4.75 [en] (X11; U; Linux 2.2.16-22 i686) Pragma: no-cache Host: www.cslab.vt.edu Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, image/png, */* Accept-Encoding: gzip Accept-Language: en Accept-Charset: iso-8859-1,*,utf-8 Proxy-authorization: Basic c3Rld2FydGI6b21keXlqcnkubQ== HTTP/1.1 200 OK Via: 1.1 DONCARLUCCI Proxy-Connection: Keep-Alive Content-Length: 14 Content-Type: text/html Date: Tue, 24 Oct 2000 17:33:00 GMT Server: Apache/1.3.12 (FreeBSD) PHP/3.0.16 mod_ssl/2.6.4 OpenSSL/0.9.4 Last-Modified: Mon, 23 Oct 2000 22:42:44 GMT ETag: "38b26-e-39f4bee4" Accept-Ranges: bytes Keep-Alive: timeout=15, max=100 session complete %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Ok, now we do it again with mozilla. GET http://www.cslab.vt.edu/~rostewa2 HTTP/1.0 Host: www.cslab.vt.edu User-Agent: Mozilla/5.0 (X11; U; Linux 2.2.16-22 i686; en-US; m18) Gecko/20001023 Accept: */* Accept-Language: en Accept-Encoding: gzip,deflate,compress,identity Keep-Alive: 300 Connection: keep-alive HTTP/1.1 407 Proxy authentication required Proxy-Authenticate: NTLM Proxy-Authenticate: Basic realm="192.168.11.5" Content-Length: 503 Content-Type: text/html Error 407

HTTP Error 407

407 Proxy Authentication Required

You must authenticate with a proxy server before this request can be serviced. Please log on to your proxy server, and then try again.

Please contact the Web server's administrator if this problem persists.

session complete %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Mozilla just stops. It does not seem to recognize that it needs to get authentication information from the user and send it to the proxy. But more interestingly, it displays nothing on the window. So the user does not even get the benefit of knowing that proxy authentication is required. So mozilla seems to detect the need for authentication, but just isn't doing about with it.