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0answers
17 views

Postfix vs stunnel relay but outlook client can't sent

I have a problem after setup postfix vs stunnel is relay host: client outlook --->[postfix:25 relay to stunnel:1125]--->smtp.vt.com.vn:465 I can sent email via postfix with telnet command but ...
0
votes
0answers
14 views

How can you enable SASLv2 and STARTTLS on a VPS? [closed]

I have tried following this guide for setting up phpbb3 email, but I got stuck on the step for enabling SASLv2 and STARTTLS. I'm not sure how to complete that step without detailed instructions. Can ...
0
votes
1answer
41 views

Exim client not issuing STARTTLS when connecting to smarthost

I have a Debian8 server running exim4 that sends outgoing mail by smarthost through NameCheap's mail.privateemail.com smtp server - or at least it use to. After a recent update, the server no longer ...
0
votes
1answer
112 views

ssmtp settings for namecheap: Invalid response SMTP Server (STARTTLS)

I am trying to configure ssmtp to use the namecheap smtp server to send emails. My current configuration: root=my@email.com mailhub=mail.privateemail.com:465 rewriteDomain=email.com hostname=email....
0
votes
1answer
65 views

How to force STARTTLS in Exim?

I am learning to set up a mailserver. I got it working with postfix, now trying the same configuration with Exim. How can I force a client to take up only STARTTLS connection for SMTP outgoing ...
2
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0answers
40 views

Properly Configure Postfix to be secure (SASL + TLS)

I've followed online tutorials online to setup my mail server with SASL and TLS, and amavis. It all seems to works - except i can send mails even if i don't authenticate first - which is not good. I ...
0
votes
1answer
87 views

Thunderbird STARTTLS fails connecting to Cyrus-IMAP 2.2.13

Today all of a sudden my Icedove mail clients (38.7.0) ceased working using STARTTLS after I renewed the server certificate. Plain text IMAP works fine. The server logs STARTTLS negotiation failed ...
0
votes
2answers
102 views

I can't send a message with postfix. Error: “Must issue STARTTLS first”

I am novice with postfix. My goal is to use it with fan/nagios/centreon in order to receive notifications. I have tried many solutions found on this forum or thanks to google, but it didn't resolve my ...
5
votes
1answer
293 views

Postfix “Trusted TLS connection established” but “Server certificate not verified”

I´m using a Postfix TLS Policy to enforce TLS for outgoing email. Unfortunately in some cases the certificate verification fails and I don´t know why. For instance, this is an excerpt of my TLS ...
1
vote
0answers
84 views

Postfix with Dovecot Disconnects after STARTTLS on Port 25

I am having a lot of trouble setting up the Postfix to do STARTTLS. It seems that I could successfully send outgoing mail using Thunderbird. However, I can't seem to get the Postman SMTP for Wordpress ...
1
vote
1answer
54 views

Enabling STARTTLS for all on Postfix with Zarafa

I ran into a problem which I just cannot solve with just googling it - I need some expert help. My company runs it's own mailserver (postfix with zarafa groupware). We're an insurance company so we ...
0
votes
1answer
53 views

STARTTLS sendmail handshake failures on SMTP and retries

I'd like to gracefully handle sendmail STARTTLS handshake failures. On outgoing mail, it would be best if there were an immediate retry without STARTTLS in the case of failure. On inbound mail, ...
2
votes
0answers
33 views

Postfix STARTTSL works in LAN but not from external (centos 7)

if I connect in LAN on port 25 to my mailserver it offers STARTTLS telnet mailserver.com 25 Trying 192.168.0.x... Connected to mailserver.com Escape character is '^]'. 220 mailserver.com ESMTP ...
2
votes
1answer
116 views

Validate email address at my own domain with gmail

I need to have the ability to send email using gmail's web interface, but have them appear to originate from my own domain instead of originating at a gmail address. In order to do this, gmail asks ...
1
vote
0answers
15 views

Are there issues in whitelabling a SMTP server (not mine) with an A record that doesn't match 200 helo?

I know that a CNAME and a MX record can't exist on the same host. In this scenario I'm using A records to manage SMTP for 350 DNS domains. companyA.com MX myAlias.whitelabel.com companyb.com MX ...
2
votes
0answers
86 views

SVN Edge not authenticating correctly with domain controller

SVN Edge (version 4.0.10-3880.131) not authenticating correctly with domain controller. I have SVN Edge setup and working perfectly when I use LDAP Security Level of NONE.. However when set to SSL, ...
1
vote
1answer
81 views

Drop non-TLS connection on EXIM

How to restrict access to EXIM to clients with STARTTLS? I want to be able to drop non-TLS connections. Current setup: tls_on_connect_ports = 465 tls_advertise_hosts = * tls_certificate = /some/...
1
vote
1answer
220 views

How to mitigate STARTTLS MITM (downgrading and forged certificates) between email servers?

I'm not as technically inclined as most on this site so please keep that in mind. I wanted to learn more about email security so I did some research and everything is according to my understanding, ...
0
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0answers
81 views

How to make Postfix SMTP TLS Optional?

Just did an [emergency] conversion from qmail to postfix last night - but now I'm getting people complaining that mail client errors are showing up stating "no available encryption methods available" ...
0
votes
1answer
296 views

Dovecot STARTTLS fails using fetchmail

I currently try to get my own mail server up and running. So far everything seems fine as I am able to connect to this mailserver using thunderbird. The only thing I have to do is accepting my own (...
1
vote
1answer
37 views

Verify TLS encryped communication when querying LDAP server?

I have a web application (not hosted on windows) that authenticates users by querying an LDAP server (a windows domain controller). The app is configured to use STARTTLS to encrypt communication with ...
-1
votes
1answer
151 views

Gitlab with OpenLDAP secured with TLS

I have a working, secure OpenLDAP server running at: auth.<company name>.com I also have a reader account that Gitlab can use: cn=Reader Reader,ou=users,dc=auth,dc=<Company name>,dc=...
0
votes
1answer
85 views

SMTP doesn't work on distinct machine [closed]

I'm trying to setup TLS e-mail on remote machine, but it doesn't work. Trying to send e-mail on my local machine (Windows 7 x64 locale ru-ru): 16:33:18 CONNECT : Looking up host name mail....
0
votes
1answer
3k views

Postfix STARTTLS only on port 25

I want to enable STARTTLS on port 25, but for unknown reasons it only works on port 465. master.cf: smtp inet n - - - - smtpd -o syslog_name=postfix/smtp -o ...
1
vote
1answer
2k views

How to disable SSLv3 in Postfix 2.11?

I just noticed (by some online check tools) that my mailserver may allow SSLv3 and updated my configuration. My current config in Postfix 2.11.2: # inbound smtpd_tls_security_level = may ...
0
votes
0answers
1k views

LDAP with TLS: connect error(-11)

I configured OpenLDAP and today I've configured the TLS for more security following these guide lines: Configure OpenLDAP with TLS=required Modifying the cn=config.ldif with config file: dn: cn=...
4
votes
1answer
3k views

Postfix Recipient address rejected: Access denied Error

Trying to use zend mail smtp to send email from my php app login authenticated and give me this constant error I don't have to deal with I look into de 36 question here on serverfault.com changing ...
2
votes
0answers
313 views

Does Google require TLS on port 587? Exchange 2010 SMTP has mail sent to GMAIL backed up in queue

Exchange 2010 SMTP has mail backed up in queue. Any email sent to Gmail sits in the queue while any email sent to another personal domain which has email filtering enabled errors, "asp.reflexion.net ...
4
votes
0answers
81 views

How can I explicitly disable TLS when sending to one specific recipient?

I have a SendMail 8.14 server deployed in the middle of an SMTP workflow (Outbound mail looks like Exchange -> SendMail -> Appliance -> Internet) I have TLS configured for the first three hosts. ...
0
votes
1answer
164 views

starttls fails after IP address change

I have changed the IP address of our exim mail server (the virtual machine has been copied to a different host, also the network configuration is using NAT). Now it no longer accepts STARTTLS ...
1
vote
1answer
168 views

How can I explicitly force SendMail to not use SSLv3 for STARTTLS connections?

SendMail 8.14.x With SSLv3 being sunset (to put it lightly), I'd like to ensure that my SendMail servers aren't using it when establishing STARTTLS connections. Is there a way I can force SendMail to ...
0
votes
1answer
236 views

Exim says “The request is invalid” during gnutls_handshake

I have Debian wheezy and setup Exim to listen to port 587, where users can authenticate using TLS. I'm testing it with Thunderbird 31.1.2. When I try to send a message, Thunderbird displays this: ...
0
votes
1answer
312 views

postfix cannot communicate with target server via TLS/SSL

I am able to connect my postfix server with TLS. All things are set up. But when i send a message with this secure connection, target server (for example gmail) receive my message without TLS/SSL ...
-3
votes
1answer
34 views

no STARTTLS in inbound email to exim [closed]

I have a CentOS VPS and I'm using Exim 4.7.2 For some days I have an issue in Thunderbird and in other client because seems STARTTLS not work in incoming email only outgoing e-mail. How can I fix ...
12
votes
2answers
866 views

Is it still “wrong” to require STARTTLS on incoming SMTP messages

According to the STARTTLS Spec Section 5: A publicly-referenced SMTP server MUST NOT require use of the STARTTLS extension in order to deliver mail locally. This rule prevents the STARTTLS ...
0
votes
3answers
2k views

Exim after Thunderbird update: “Could not negotiate a supported cipher suite” [closed]

Recently, after I installed updates on my Kubuntu 14.04. system and a new version of thunderbird was installed, I could not send emails any more. It prompts: Sending of message failed. The message ...
1
vote
1answer
5k views

Postfix still complains that “certificate verification failed” even when “smtp_tls_security_level = fingerprint”

I'm attempting to use Postfix (version 2.6.6 on RHEL6) to connect to and send mail via a mail relay on our internal network. I want to connect with STARTTLS on port 25 (port 465 is not available on ...
2
votes
1answer
1k views

How can I enforce TLS in sendmail when I don't necessarily know the hostname of the downstream MTA (only IPs)? [e.g. by recipients' domain]

I'm running SendMail 8.14 and have some custom static routes for sending to certain domains. These domains are "internal" but not managed directly by me. Here's an example of /etc/mail/mailertable:...
0
votes
1answer
389 views

SMTP Connection disconnecting after “STARTTLS”

We're having issues with our mail server. Basically some emails from external networks are not being accepted by the mailserver. After some debugging using telnet and looking through the logfiles, it ...
5
votes
2answers
4k views

ejabberd starttls_required in c2s/s2s and disable SSLv3 + unsecure Ciphers

I'm using ejabberd on Ubuntu. My configuration looks like this: {5269, ejabberd_s2s_in, [ {shaper, s2s_shaper}, {max_stanza_size, 131072}, ...
24
votes
4answers
24k views

Is STARTTLS more safe than TLS/SSL?

In Thunderbird (and I assume in many other clients, too) I have the option to choose between "SSL/TLS" and "STARTTLS". As far as I understand it, "STARTTLS" means in simple words "encrypt if both ...
1
vote
0answers
315 views

Postfix - SASLAuthentication Problems Cram-MD5 with StartTLS

Recently I configured my mail server which uses Postfix and Courier. Everything works except for the authentication when sending mail via my Postfix server(running on port 587) which has StartTLS ...
0
votes
2answers
10k views

Postfix & Gmail: Authentication Required error

I configured Postfix using this guide. When I send a test E-Mail I get the following error message: May 23 15:36:26 VM11 postfix/smtp[15321]: connect to smtp.gmail.com[2a00:1450:4001:c02::6d]:587: ...
1
vote
1answer
112 views

How can I tell if my LDAP authentications are using StartTLS?

I'm setting up a new OpenLDAP server on Ubuntu 12.04 with a copy of our current LDAP database. I've gotten most of the configuration down, I think, but I'm having trouble telling if the LDAP queries ...
1
vote
2answers
3k views

Does Exchange 2010 encrypt inbound and outbound email traffic by default?

The higher ups have recently asked about this as I'm sure there are compliance issues that need to be addressed. I was under the assumption that Exchange uses opportunistic TLS or StartTLS to try to ...
1
vote
1answer
8k views

TLS: hostname does not match CN in peer certificate

im trying to connect LDAP over StartTLS but Im stuck with an issue. I've followed step by step this guide https://help.ubuntu.com/12.04/serverguide/openldap-server.html#openldap-tls and LDAP it's ...
5
votes
1answer
1k views

postfix TLS configuration for incoming gmx-mail

I set up my mailserver with postfix 2.7.1 and dovecot 1.2.15 and everything seemed to work just fine, but now I found out that people using @gmx.net addresses cannot send emails to me and rather ...
0
votes
1answer
2k views

postfix, TLS and rapidssl - “verify error:num=19:unable to get local issuer certificate”

I have a certificate from rapidssl. I run this command: openssl s_client -showcerts -connect smtp.server.com:465 I get this error: verify error:num=19:self signed certificate in certificate chain ...
2
votes
2answers
647 views

How do I log tls-encrypted smtp traffic?

I'd like to know what my local postfix says to the Amazon SES smtpd after the STARTTLS. In plain text, so I can understand it. Amazon SES requires TLS, so I can't temporarily turn it off. I currently ...
2
votes
2answers
2k views

SMTP server requires STARTTLS

I am using fetchmial. Below is my configuration. I want the retrieved emails to be sent to my gmail address. But I encountered an error below. Could someone help me with this? Thank you in advance. ...