We had Squid 2.6.Stable21 running on an EL 5 server. Due to some new requirements we needed to build a new server with EL6. This came with Squid 3.1.10 Copying the old config file to the new server hasn't worked. We have had to comment out some lines which the new version no longer supports. Squid is now able to start but every time we try to connect to an external host we receive TCP_MISS/503 and TCP_MISS/404 errors in the access log. Here is the config from the EL5 server. What need to be corrected to get this to work as before? NOTE: We can switch to the EL5 server and connect without issue so it is clearly an issue with the upgrade from 2.6.x to 3.1.x #Recommended minimum configuration: 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 CONNECT method CONNECT http_access allow all http_access allow manager localhost http_access deny manager http_access deny !Safe_ports http_access deny CONNECT !SSL_ports http_access allow localhost http_access deny all icp_access allow all http_port 8021 hierarchy_stoplist cgi-bin ? access_log /var/log/squid/access.log squid acl QUERY urlpath_regex cgi-bin \? cache deny QUERY refresh_pattern ^ftp: 1440 20% 10080 refresh_pattern ^gopher: 1440 0% 1440 refresh_pattern . 0 20% 4320 acl apache rep_header Server ^Apache broken_vary_encoding allow apache coredump_dir /var/spool/squid Thanks in advance Rich Gomes | Senior Systems Administrator, AUCA System Services | ARAMARK Uniform & Career Apparel Tel: 781.763.4508 | Fax: 781.763.2508 Rich.Gomes@xxxxxxxxxxxxxxxxxxx | www.aramark-uniform.com