After the synchronization of contacts with Outlook was turned on, the following dialog pops up while Outlook synchronizes emails.
All versions of eWay-CRM
The issue is related to the setting of junk email (Junk E-mail > Junk E-mail Options) where the Also trust email from my Contacts checkbox is marked.
Outlook limits number of addresses on the list, so after new contacts from eWay-CRM were added the limit was reached. Just unmark the Also trust email from my Contacts checkbox.