Administrators • Failure to connect to a fresh instance

Gents,
Here I have a newly installed Zimbra v.8.8.15 on a CentOS 8 VM. In the same virtual network there is a SBS2003 (it's a testing environment for developing a migration procedure). SBS hosts example.local and its name is main.example.local. Zimbra has the name mail.example.com. There is a forwarding zone example.com configured on SBS with all the necessary requisites. Zimbra has the domain set with authentication against SBS.
Zimbra is configured with letsencrypt certificate. After this it was restarted a couple of times, so it should be applied already.
So, there is a W7 workstation in the same virtual network. When I try to configure Outlook 2010 with the Zimbra with IMAP I get failures:

• on IMAP "None of the authentication methods supported by your IMAP server (if any) are supported on this computer";

• on IMAP + SSL:993 "A secure connection cannot be established";

• on IMAP + TLS:143 the same as previous "...secure connection...";

• on SMTP:587 "The server responded: 554 5.7.1 <unknown[192.16" (I guess this is truncated);

• on SMTP + SSL:465 ""Your server does not support the connection encryption type you have specified...".

The only protocol:port that works is SMTP:25.
I think that the cyphers I use are configured wrongly, although I did not configure something special, just attached the certificate and configured authentication vs. domain.
What could be wrong with my installation?

Statistics: Posted by imarine — Thu Dec 21, 2023 11:24 am

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