At the bottom of your Office 365 Primary or shared mailbox, you may see the message "currently displaying all messages newer than 12 months". To extend this duration, action as follows:
Open Outlook
On the toolbar, select FILE > ACCOUNT SETTINGS
Click ACCOUNT SETTINGS ...
From the ACCOUNT SETTINGS screen, double-click your email address beneath "Name"
You will now see this box:
Drag the blue bar across to the right, until the word "ALL" appears:
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Click NEXT
Click DONE > CLOSE
Close and re-open Outlook. Your historic emails will now be visible.
If issues persist after following these instructions, please contact our Help Team on 01933 229133.