Hi, I'm running squid-2.5.STABLE6-3.4E.12 and samba-3.0.10-1.4E.9 on CentOS 4.4, all is working fine but I don't understand how to configure external ip_user_check with AD group: [root@SRV ~]# wbinfo -g|grep -i internet MyADD\Internet-l1 MyADD\Internet-l2 MyADD\Internet-l3 [root@SRV ~]# winbind separator = \\ [root@SRV ~]# less /etc/squid/ip_user_check.conf # L3 192.168.1.19 MyADD\\foo 192.168.1.18 MyADD\\bar # L2 192.168.1.0/255.255.255.0 @MyADD\Internet-l2 0.0.0.0/0.0.0.0 NONE [root@SRV ~]# echo "192.168.1.9 @MyADD\Internet-l2"|/usr/lib/squid/ip_user_check -f /etc/squid/ip_user_check.conf ERR [root@SRV ~]# echo "192.168.1.19 MyADD\\\foo"|/usr/lib/squid/ip_user_check -f /etc/squid/ip_user_check.conf OK Why ?