what i feel is : access is denied as remote user may not be able to access the database. i think when any user does login through proxy, the effective user is squid. i gave permission to squid user also for select. i.e. grant select on squid.* to squid@localhost identified by 'squid'; is it the problem because squid user doesn't have "login" shell permission? answers are with your questions: > Please describe: > what version of Squid this is? squid-3.1.0.14 > did the troubleshooting tests described at the end of example work? yes, at the end of example whatever command is given works perfectly ok. > how does your browser connect to the proxy? browser prompts for username and password. > what happens when you try to login? after entering username and password it again and again asks for the same. squid's access log shows like 1272114337.269 0 172.16.1.108 TCP_DENIED/407 4297 GET http://sb.google.com/safebrowsing/update? - NONE/- text/html > what do your full http_access rules look like? acl localnet src 172.16.1.0/24 auth_param basic program /usr/lib/squid/squid_db_auth --user someuser --password xxxx --plaintext --persist auth_param basic children 5 auth_param basic realm Web-Proxy auth_param basic credentialsttl 2 hours auth_param basic casesensitive off acl db-auth proxy_auth REQUIRED http_access allow db-auth http_access allow localhost http_access allow localnet http_access deny all