Try these steps in order:
- Close Outlook and all other Office apps completely, then reopen Outlook.
- A known Outlook issue can cause hosted apps opened from the left menu to show a blank screen.
- Confirm the correct account is signed in.
- In Outlook, make sure the signed-in Microsoft 365 account is the one that has the Copilot entitlement.
- For work or school accounts, Copilot Chat in Outlook is accessed by signing in with that work or school account and selecting the Copilot button in the upper region of Outlook.
- Refresh the Microsoft 365 license.
- On Windows: in any Microsoft 365 app, go to File > Account > Update License.
- Close and restart all Microsoft 365 apps after the refresh.
- Update Office to the latest build.
- Microsoft recommends being on the latest build when the Copilot button is missing or not working correctly.
- If using Outlook on the web, refresh the browser page.
- If it still does not work, third-party cookies being blocked can prevent Copilot from validating the license.
- If the issue started recently in classic Outlook, there has been a reported service issue where some users could not see or open the Copilot button in Outlook clients.
- Restarting Outlook after the service-side fix rollout was the recommended action in that case.
If the Copilot pane is still blank specifically from the left-side Outlook menu after these steps, the most directly supported workaround is to fully close Outlook and relaunch it.
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