Outlook Integration icons are grayed out in Outlook when composing a new email.
ROOT CAUSE
Another app from Office store is providing the same functionality like Outlook Integration or Inbox is causing a conflict and causing the Outlook Integration button to be grayed out in the new email compose window.
User can try the below steps:
If not composing a new email, refer to this article on Outlook Integration or Salesforce Inbox App Icons Grayed Out in Outlook.
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