Hi, I have Sendmail configured to use STARTTLS for authentication. On all internet connections and computers (that I have tested) works connection over encrypted SMTP flawlessly. Today I was setting up mail client on PC of my customer and standardily checked boxes, that I want to use SSL for POP3 and SMTP. Next I wanted to check configuration (by sending email from this mailbox to this mailbox) but it does not work. So I have opened telnet, connected via port 25 and writed "ehlo hostname" and then finded out, that there is missing STARTTLS. Is possible, that some bad configuration on client side (firewall, etc...) can cause this error including that this function is missing in printout of ehlo? POP3S working good. >From Sendmail log (/var/log/maillog): Nov 28 19:31:23 server sendmail[11163]: xxx: xxxxx.jizmorava.adsl-llu.static.bluetone.cz [85.207.xxx.211] did not issue MAIL/EXPN/VRFY/ETRN during connection to MTA Thank you very much