If you use Easy2Sync für Outlook for the first time, your data storages (PST files, Exchange accounts) might already be identical. This will make the first sync faster, but it is not required. If the data storages are different, Easy2Sync will simply copy all missing folders, e-mails, contacts, etc. to the respective other side.

Easy2Sync never deletes data during the first sync.

Synchronize Outlook