Error errorunsupportedpropertydefinition when syncing mail

I can’t get new email on my kerio account, I’m getting this error everytime it tries to sync mail, already deleted my account and reconfigured, it synced twice but then I got the same error, I would appreciate some help on this issue, thanks.

First thing to check is that you have the correct settings. The host name you will get from your provider, and the port and security settings should be one of the following combinations.

SMTP
Port 587 = Force usage of SSL/TLS
Port 25 = Use SSL/TLS if available
Port 465 = Use SSL/TLS on special port (legacy)

IMAP
Port 993 = Use SSL/TLS on special port (legacy)
Port 143 = Use SSL/TLS if available

POP3
Port 995 = Use SSL/TLS on special port (legacy)
Port 110 = Use SSL/TLS if available

These are the correct combinations of port and security policy. The underlined ones are the best option for security if your server supports them. SMTP port 465 was reassigned and should no longer be used for SMTP, though many mail providers still recommend and use it.

Thanks for your reply, this is a kerio account, and like so it’s treated like an exchange account, not as IMAP account, so I have no setting to change ports.

Yes João, you are correct you cannot change the settings for Exchange. If this is for your work email, I suggest you open a support ticket with eM Client as it is unlikely you will get much help with Exchange on this forum.