How to fix the missing Copilot integration in Outlook?

Hello,

A few details would help narrow this down. Which Microsoft 365 subscription do you have exactly? "Microsoft 365 Premium" can refer to different products, and Copilot availability in Outlook depends on the subscription and account type.

You could also check if : 

• Copilot is still available in Word, Excel, or PowerPoint. 
• You're using Classic Outlook, New Outlook, or Outlook on the web. 
• Copilot appears in Outlook on the web. If it does, that would suggest the issue is specific to the Outlook desktop client rather than your license. 
• Outlook is connected using an Exchange account rather than POP or IMAP. There have also been cases where Copilot buttons were missing or unavailable in specific Outlook versions, so your Outlook version and build number would be useful as well.
• You could also try signing in to Outlook on the web using an InPrivate/Incognito browser session. If Copilot appears there, that would help determine whether the issue is related to the Outlook desktop client, browser cache, or account configuration.

If you can share your subscription, Outlook version, and whether Copilot still works in the other Microsoft 365 apps, it should be easier to determine whether this is a licensing issue, an Outlook client issue, or something related to the reinstall.

Hope this helps