Cannot Connect To Smtp Server Connect Error 10061 Postfix
Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads with us Server Fault Questions Tags Users Badges Unanswered Ask Question _ Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute: Sign up Here's how it works: Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top Postfix & TLS is configured correctly, but Thunderbird throws cryptic errors when trying to send email via SMTP & STARTTLS? up vote 1 down vote favorite I've just recently installed CentOS 5.5 and Postfix for the first time ever. I've followed 2 different tutorials which are supposed to enable TLS on the SMTP server. Both of which told me to create a key & cert, edit the config, test the server by connecting via telnet. Everything looks like it should be working. When I connect with telnet, the server advertises that I can connect with STARTTLS. I have opened the firewall for both ports 25 & 465. SELinux is disabled (not sure if that would have interfered or not). When I attempt to send an email with STARTTLS enabled in Thunderbird, I am given the following error: An error occurred sending mail: The mail server sent an incorrect greeting: Cannot connect to SMTP server 192.168.0.9 (192.168.0.9:465), connect error 10061. After pressing OK, I am greeted with another, less helpful message: Sending of message failed. The message could not be sent because the connection to SMTP server cinc.centos was lost in the middle of the transaction. Try again or contact your network administrator. I've Googled and fiddled with the configuration hour the best part of a day now. And I've got absolutely no closer to fixing it. I've tried Googling the error message, or just the error code, and it hasn't found anything helpful. However.. the SMTP server works perfectly fine without any TLS encryption! So the error definitely is just with encryption, hence why the error message mentions port 465. In case it helps, I've posted the TLS part of my main.cf: smtp_tls_note_starttls_offer = yes smtpd_tls_received_header = yes smtpd_sasl_local_domain = cinc.centos smtpd_sasl_auth_enable = yes smtpd_sasl_security_options = noanonymous broken_sasl_auth_clients = yes smtpd_recipient_restrictions = permit_sasl_authenticated,permit_mynetworks,reject_unauth_destination smtpd_tls_security_level = may smtpd_tls_
Fedora Arch SERVERS Apache Nginx Email FRAMEWORKS Ruby on Rails Capistrano Django SLICE ADMIN SliceManager Slice Admin Backup Security OTHER MySQL PostgreSQL Email Subversion SSH Windows CentOS - Mail Server - Secure Connection, Configuring Postfix Now that we've created our self-signed certificate (see the previous article) we can go ahead and configure Postfix to use it. Main.cf As with the previous Postfix configuration, we need to edit the main.cf file: sudo nano /etc/postfix/main.cf TLS Parameters Towards the bottom of this file we will add the following TLS parameters: smtpd_tls_security_level = may smtpd_tls_key_file http://serverfault.com/questions/169180/postfix-tls-is-configured-correctly-but-thunderbird-throws-cryptic-errors-whe = /etc/pki/tls/private/mail.demoslice.com.key smtpd_tls_cert_file = /etc/pki/tls/certs/mail.demoslice.com.cert smtpd_tls_loglevel = 1 smtpd_tls_session_cache_timeout = 3600s smtpd_tls_session_cache_database = btree:/var/spool/postfix/smtpd_tls_cache tls_random_source = dev:/dev/urandom Good. Settings Now let's take a quick look at what we have done to get a basic grasp on what each setting accomplishes. Smtpd tls security level The security level setting allows us to enable the use of TLS to encrypt our SASL authentication sessions. The use of http://articles.slicehost.com/2009/9/29/centos-postfix-secure-connection-configuring-postfix 'may' in this setting replaces the deprecated use of 'yes' in older versions of Postfix. smtpd_tls_security_level = may Smtpd tls key file and Smtpd tls cert file These options, while somewhat self-explanatory, would be used to specify the location of the self-signed certificate as well as the key file we generated in the previous article (link). smtpd_tls_key_file = /etc/pki/tls/private/mail.demoslice.com.key smtpd_tls_cert_file = /etc/pki/tls/certs/mail.demoslice.com.cert Smtpd tls loglevel If TLS is not working properly, how are we going to know what the problem is? Simple. We can gather further information by setting the loglevel to 1 as it will log TLS sessions to the postfix mail log. smtpd_tls_loglevel = 1 Smtpd tls session cache Repeatedly negotiating TLS session keys for each connection we make to the mail server can be quite tedious and cause considerable strain on our slice. To resolve this issue, we are going to cache the sessions for 3600s or 1 hour. smtpd_tls_session_cache_timeout = 3600s Everything sound good so far? Great, now we can enable these settings and then give it a quick test run. Reload As with any changes we make to the Postfix configuration, we need to perform a reload b
the new Plesk version coming out later this year. Visit this thread for more details. https://talk.plesk.com/threads/cannot-connect-to-smtp-server-outgoing-mail.59367/ Cannot connect to SMTP server (Outgoing Mail) Discussion in 'Plesk for Linux - 8.x and Older' started by acidbox, Sep 6, 2005. acidbox Guest 0 I am having http://www.pc-freak.net/blog/what-causes-the-421-cannot-connect-to-smtp-server-error-and-a-quick-work-around/ trouble connecting to the outgoing mail server (SMTP) on my plesk 7.5.4 server. In outlook I get this: Outlook is unable to connect to your outgoing (SMTP) e-mail server.Click to cannot connect expand... Then if I try to telnet to the server, I get this: 421 Cannot connect to SMTP server xx.xx.xx.xx (xx.xx.xx.xx:25), connect error 10060Click to expand... I Opened port 587 in my firewall to try to send mail through an alternate port SMTP will not recognize it. When I try to telnet, I get the following: Connecting To mail.mydomain.com...Could cannot connect to not open connection to the host, on port 587: Connect failedClick to expand... Also, there are no errors or connection failures in /usr/local/psa/var/log/maillog Does anyone know why this is happening and how to fix it? acidbox, Sep 6, 2005 #1 jamesyeeoc Guest 0 I Opened port 587 in my firewall to try to send mail through an alternate port SMTP will not recognize it.Click to expand... Other than just opening the port, what configurations did you do to tell SMTP to listen/accept on that port? Was the Outlook error code one of the following: • 0x800ccc15 • 0x80042108 • 0x800ccc0e • 0x8004210b • 0x800CCC0B • 0x800CCC79 • 0x800ccc67 • 0x80040900 (all these indicate no response from mail server) Try telnet'ing to your server on port 25 and 587 to see if you get any response. Post results here. From a SSH root login, see if Qmail and/or IMAP are running in memory: ps -ax |grep 'qmail' ps -ax |grep 'imap' jamesyeeoc, Sep 6, 2005 #2 acidbox Guest 0 Thanks for th
A colleague of mine has encounters errors like: An unknown error has occurred. Account: ‘mail.different.bg', Server: ‘mail.different.bg', Protocol: SMTP, Server Response: ‘421 Cannot connect to SMTP server 212.70.124.241 (212.70.124.241:25), connect error 10060', Port: 25, Secure(SSL): No, Server Error: 421, Error Number: 0x800CCC67 while he was trying to send some emails with his Outlook Express mail client on his desktop computer running Windows XP, since he is not too much computer literate he contacted me for help on what is causing the error and how he can get through the issue and send the prepared emails to the destinations ASAP. After I have asked him a few questions necessary to better understand the status of the problem and where does it originated I have come to the conclusion that it's very likely that his outgoing SMTP port (25) outgoing TCP/IP traffic passing through the Internet Service Provider is filtered. When the 421 Cannot connect to SMTP server problem occured, he was actually in his parents house provided with an internet connection through a BTC ADSL see BTC (Vivacom)'s ADSL page for reference I have instructed my friend to try connecting to the SMTP (25) port of the questionable email server using window's telnet client i order to check if my assumption that the outoging SMTP 25 port traffic is filtered. I instructed him to issue a command like which is so common this days and it's not news to the Sysadmins out there: cmd> telnet mail.server.net 25 This prooved my theory that the 421 Cannot connect to SMTP server was caused by a filtered traffic on the outgoing network STMP port (25). Some Internet Providers out there has that annoying practice of filtering the outgoing SMTP connections, because they couldn't deal with infected Windows com