For some accounts (especially emails received outside organization/internal domain) the activity Get Outlook Emails is unable to retrieve Sender information. When trying to retrieve mail.sender or mail.from objects it results with a NULL value, all other objects(mail.body,mail.attachment, headers etc) are available. In the Outlook application, sender information is available.
Check the following settings to disable the Outlook Caching (can be temporary disabled to see the outcome and then enabled but with reduced time gradually):
- In Outlook, select “File” > “Account Settings” > “Account Settings“.
- Select the Exchange account in the list under the “E-mail” tab, then select “Change…“.
- Check the “Use Cached Exchange Mode” box to enable it. Uncheck it to disable it.
When enabled you can use the slider to select how much mail you wish to keep offline. You can also select the “More Settings…” button and choose other Cached Exchange Mode settings under the “Advanced” tab.