Hi, all If the icap server(reqmod) responses the following, HTTP/1.0 407 Proxy Authentication Required Proxy-Authenticate: Basic realm="XXXXX" squid try to delete the Proxy-Authenticate header .... > client_side_reply.cc > 1218 // if there is not configured a peer proxy with login=PASS option enabled > 1219 // remove the Proxy-Authenticate header > 1220 if ( !(request->peer_login && strcmp(request->peer_login,"PASS") ==0)) > 1221 reply->header.delById(HDR_PROXY_AUTHENTICATE); The above codes is that. For your information, squid 3.0 is no problem. What do you think ? Squid version: 3.1.6 Sincerely, -- Mikio Kishi