Hello, I am trying to get ntlm_auth to work in my squid-2.6.STABLE21-6.el5 installation on RHEL 5.4. Samba is samba-common-3.0.33-3.15.el5_4. Here's my relevant config: auth_param ntlm program /usr/bin/ntlm_auth --helper-protocol=squid-2.5-ntlmssp auth_param ntlm children 5 auth_param basic program /usr/bin/ntlm_auth --helper-protocol=squid-2.5-basic auth_param basic children 5 auth_param basic realm Squid proxy-caching web server auth_param basic credentialsttl 5 hours acl all src 0.0.0.0/0.0.0.0 acl manager proto cache_object acl localhost src 127.0.0.1/255.255.255.255 acl to_localhost dst 127.0.0.0/8 acl SSL_ports port 443 acl Safe_ports port 80 # http acl Safe_ports port 21 # ftp acl Safe_ports port 443 # https acl Safe_ports port 70 # gopher acl Safe_ports port 210 # wais acl Safe_ports port 1025-65535 # unregistered ports acl Safe_ports port 280 # http-mgmt acl Safe_ports port 488 # gss-http acl Safe_ports port 591 # filemaker acl Safe_ports port 777 # multiling http acl NTLMUsers proxy_auth REQUIRED http_access allow manager localhost http_access deny manager http_access deny !Safe_ports http_access deny CONNECT !SSL_ports http_access allow NTLMUsers http_access deny all Using IE or Firefox, I am presented with an authentication dialog box. I attempt to authenticate and it fails. In the logs, I see only this: 1274715773.285 1 10.98.1.122 TCP_DENIED/407 1813 GET http://google.com/ - NONE/- text/html I am able to authenticate fine manually: [root@omajelut01 ~]# ntlm_auth --username=john --domain=DOMAIN1 password: NT_STATUS_OK: Success (0x0) Where am I going wrong here?