Exchange Server using Outlook
MailtoX can download email messages from Exchange Server and Office 365 via Outlook. It uses MAPI to access Outlook.
Before exporting email from Exchange make sure that the messages have been downloaded locally by Outlook.
Cached Exchange Mode
Set the option "mail to keep online" to All.
Send / Receive Groups
Outlook has the option to setup the folders that will be synchronized when you press Send/ receive All Folders
You can create a new group or use the existing default one:
Select the folders that you plan to export (1) and make sure that the option to "Download complete item including attachments" (2) is selected.
When you press on Send/ receive All Folders all the email messages in the folders that you have defined will be downloaded to *.ost files.
Force Online Option
MailtoX has the option to download the missing messages, the ones that have not been downloaded by Outlook.
It is better to let Outlook download the messages because they might have been partially downloaded by Outlook (only the headers).