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In Outlook, choose File and then Options.
Select the Add-ins tab of Outlook Options dialog box.
Confirm that Microsoft Teams Meeting Add-in for Microsoft Office is listed in the Active Application Add-ins list
If the Teams Meeting Add-in is listed in the Disabled or Inactive Application Add-ins list, select it, then select COM Add-ins in Manage and then select Go…Set
Select the checkbox next to Microsoft Teams Meeting Add-in for Microsoft Office.
Choose OK on all dialog boxes and restart Outlook.
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