Hi List, I have a postfix server based on CentOS 5 in which I have been trying to add TLS encryption support for SMTP. From the localhost when I do an EHLO, following is the output [root at xxxxxxx ~]# nc localhost 25 220 xxxxxxx.xxxx.xxx.xx ESMTP Postfix EHLO localhost 250-xxxxxxx.xxxx.xxx.xx 250-PIPELINING 250-SIZE 41943040 250-VRFY 250-ETRN 250-STARTTLS 250-AUTH PLAIN LOGIN 250-AUTH=PLAIN LOGIN 250-ENHANCEDSTATUSCODES 250-8BITMIME 250 DSN However from a remote location when I do the EHLO, the response does not contains STARTTLS, ENHANCEDSTATUSCODES and DSN krishna at L03:~$ nc xxxxxxx.xxxx.xxx.xx 25 220 xxxxxxx.xxxx.xxx.xx ESMTP Postfix EHLO localhost 250-xxxxxxx.xxxx.xxx.xx 250-PIPELINING 250-SIZE 41943040 250-VRFY 250-ETRN 250-AUTH PLAIN LOGIN 250 8BITMIME I have done some googling and found this might be because of the Cisco Router's "ESMTP Fix". However Can someone here tell me if there are any settings in master.cf or main.cf that might result in similar behaviour? Regards, KRiSHNA