On 31-5-2020 06:36, Mark Constable wrote:
I currently use Ubuntu 20.04 with Dovecot 2.3.7.2 and OpenSSL 1.1.1f.
A few months ago there was an update to all these systems and since then I've had to talk W7 and old Mac clients through disabling ports 993/995 with TLS enabled back to ports 143/110 without SSL or they could not pick up email. Thunderbird users (ie; me) were unaffected.
Could anyone share a set of port 993/995 SSL settings known to work with Windows7 and Outlook16 using "dovecot -n|grep ^ssl_" please ?
Mine is currently...
ssl_ca = </etc/ssl/certs/ca-certificates.crt ssl_cert = </etc/ssl/example.com/fullchain.pem ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it ssl_options = no_compression no_ticket ssl_prefer_server_ciphers = yes
I have commented out ssl_cipher_list, ssl_min_protocol and others to get back to whatever the defaults are so I am not simply guessing what the optimal settings would be to cover Win7 and up.
Yes I know Win7 is no longer supported but that does not help the 100s of older users I have that can't/won't upgrade their computers.
Did you enable TLS1.2 in Windows 7?
https://support.microsoft.com/en-us/help/3140245/update-to-enable-tls-1-1-an...
(or, not tested on Windows 7: https://www.nartac.com/Products/IISCrypto/ )