This option is typically only necessary when syncing to Google or Exchange. Enable 'Sync Attendees' if you want attendee data to sync with your calendar records. Enter the date range for the number of past days to sync. Due to macOS limitations SyncMate only syncs with online Outlook accounts; sync with desktop Outlook app for Mac is not supported at this time. Sync your Outlook contacts with Mac Address Book. We strongly recommend you to do a backup before your first synchronization. Download and install SyncMate on your Mac. Once the installation is complete.
If you want to have all your Outlook contacts available in your Apple's Mail application on your Mac, you'll need to get them all into the Contacts app. This entails a two-phase process. In the case of your Outlook address book, you'll have to save your contacts to a comma-separated value (CSV) plain-text spreadsheet—a format that's readily understood across both apps.
Then, the application, which Mail uses for contacts management, can import the file and organize its contents with nary a hiccup.