Use of eM Client for testing new Exchange Server / Clarification on Accounts Settings / How-To activate use of SMTP-Auth-Mechanism NTLM

Dear all,

currently I`m using eM Client to “debug” / “test” a new Exchange 2016-Server from work and its configuration.

At the moment it seems that the Exchange-Server is not offering all possible settings it could offer.For example EWS (= standard way of eM Client to communicate with an Exchange-Server) is not reachable from the outside world at the moment.

I continued to test the server for IMAP(S) and SMTP(S) setup.

Ports with implicit TLS are standardised as:
SMTPS (465)
IMAPS (993)
POP3S (995)

In the account settings there is a dropdown filed named “Sicherheitsrichtlinie” (= sorry using german GUI-language) which offers different options to choose from.

Maybe eM client Support could shed light on what each option does exactly (lets stick on IMAP(S)-Protocol for this clarification question):
“Keine sichereVerbindung verwenden” (= Do not use a secure connection) > This one is clear (and of course should not be used nowadays).
"SSL/TLS verwenden, wenn verfügbar (= Use SSL/TLS if available) > Text is also clear; what port will this option use if nothing or the wrong port is set (or will it decide whether to use SSL/TLS based on the given Port; e.g. if Port set to 993 TLS will be used, if Port set to 143 no encryption will be used)?
“SSL/TLS erzwingen” (= force SSL/TLS) > Text is also clear; what will happen here if no or wrong Port is set?
“SSL/TLS auf bestimmten Port verwenden (Legacy)” (= Use SSL/TLS with a specific port (Legacy)) >This one is to most difficult to understand form my point of view;but its the one I use at the moment and set to 993 for IMAP(S) to be used >> Also this setting works for the server I`m dealing with

Next question:
For SMTP(S) I have had no success in establishing a connection > I assume that our new Exchange 2016 will only accept the SMTP-Auth-Mechanism of NTLM at the moment.

Ho do I activate NTLM for an account?

Best regards,

Anti-virus, firewall, proxy or VPN can block the connection, so sometimes you have the correct settings, but cannot connect. As a test, completely disable these and see if there is any difference.

With the settings in eM Client, the port and security policies are specific pairs, so having the correct combination may help:

Port 587 = Force usage of SSL/TLS
Port 25 = Use SSL/TLS if available
Port 465 = Use SSL/TLS on special port (legacy)

Port 993 = Use SSL/TLS on special port (legacy)
Port 143 = Use SSL/TLS if available

Port 995 = Use SSL/TLS on special port (legacy)
Port 110 = Use SSL/TLS if available

Hi Gary,

thanks for your help.
Yesterday I was able to send by using the right combination of Port 587 with option “Force usage of SSL/TLS”.

Do you personally know which SMTP-Auth-Type ( eM Client uses by default?

And where to set another SMTP-Auth-Option; for example NTLM?


eM Client looks at what the server offers, and chooses the most secure option.

So it depends on what your server offers. It is not possible to configure this manually in eM Client.