IMAPPRO is not working since yesterday

IMAPPRO is not working since yesterday

Imap connection/sync with outlook2013 is not working since yesterday Error="is not possible to stablish conection with server". I'm unable to download emails to outlook.
I've tried to change imappro to imap but the results are the same.
smtp is working fine.

Coul you please help in troubleshoting this?
Thanks