Outlook and TLSv.1

[Robert Schetterer]

Am 16.01.2015 um 12:24 schrieb Oliver Welter:
> Hi Folks,
> 
> after adding TLSv1.2 to by TLS options a lot of Outlook users complaint
> about connection errors, openssl s_client and Thunderbird works fine.
> 
> I found some posts about this but none of them had a real solution on
> this - I meanwhile disabled TLSv1.2 which made the Outlook users happy.
> 
> I run dovecot 2.2.13, OpenSSL 1.0.1j 15 Oct 2014
> 
> ssl_cert = </var/qmail/control/servercert.pem
> ssl_cipher_list = ALL:!EXPORT:!LOW:!MEDIUM:!aNULL:+RC4:@STRENGTH
> ssl_dh_parameters_length = 2048
> ssl_key = </var/qmail/control/servercert.pem
> ssl_protocols = !SSLv2 !TLSv1.2
> 
> The certificate is from Comodo using sha256.
> 
> Any idea?
> 
> Oliver
> 

there is no "Outlook", please do a exact debug what Outlook and Windows
Version, disable TLSv1.2 is a bad idea, my bet goes on your
ssl_cipher_list, try this

# SSL ciphers to use
ssl_cipher_list = ALL:!LOW:!SSLv2:!EXP:!aNULL


or search list archive and www for other better solutions and general
dovecot ssl configs


Best Regards
MfG Robert Schetterer

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