Outlook Express and STARTTLS

Oscar del Rio delrio at mie.utoronto.ca
Fri Nov 21 22:35:00 UTC 2014

On 11/21/14 04:29 PM, Reindl Harald wrote:
> the situation for Outlook (not OE) and TLS is not much better
> some versions support STARTTLS on SMTP but not for IMAP/POP3 ...

Outlook (at least since version 2010) does support STARTTLS for IMAP/POP3 on 
port 143.
But they don't call it STARTTLS but "TLS". And they call "SSL" to TLS on port 

With Outlook configured for "TLS" on port 143:
outlook -> dovecot: a0gk CAPABILITY
dovecot -> outlook: * CAPABILITY IMAP4rev1...STARTTLS...
outlook -> dovecot: h96q STARTTLS
dovecot -> outlook: h96q OK Begin TLS negotiation now
(TLS starts)

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