Mozilla Thunderbird
Thunderbird provides a wizard that tries to lookup and suggest configuration values for the incoming and outgoing server.
Note
At this time Kopano Cloud does not support fully automatic configuration of Thunderbird. Instead, the account must be configured manually.
To get to a working account in Thunderbird, the "hostname" must be set to kopano.cloud. For the incoming server, the connection needs to use SSL/TLS on port 993 and for the outgoing server, the connection needs to be set to STARTTLS on port 587. And after running a "Re-test", Thunderbird will allow the account to be created and unblock the "Done" button.
With this the account can be used to send and receive mails. Further features like calendar or contact access for Thunderbird are currently not offered by Kopano Cloud, but we received positive feedback for using the TB-Sync Thunderbird addon to retrieve these via ActiveSync.