Question / Problem:
The customer wants to poll emails from a Kerio Connect email server via EWS (Exchange Web Services).
Is this supported?
Answer / Solution:
This scenario is not supported.
Kerio Connect has developed it's own version of EWS which isn't fully compatible with the EWS standard developed by Microsoft.
KIC/KTA only supports EWS mail polling from a Microsoft Exchange email server.
Use POP3 or IMAP to poll mails from a Kerio Connect email server.