Microsoft fixes classic Outlook bug that hid Copilot buttons
Microsoft has fixed a known issue that removed the Copilot Chat and Copilot buttons in the classic Outlook desktop mail client for some Windows users.
Microsoft has fixed a known issue that removed the Copilot Chat and Copilot buttons in the classic Outlook desktop mail client for some Windows users.
As explained in an updated support document , affected users with the Copilot Chat (Basic) license or a Microsoft 365 Copilot (Premium) account no longer saw Copilot buttons in the side navigation and above the ribbon.
Those impacted by this experienced one or more of the following issues: Microsoft first announced in June that it had fixed the bug with a service change, but last month it said it had started investigating again after recent updates caused it to resurface.
Microsoft also shared a temporary workaround for those still affected by this known issue, which requires enabling the option in classic Outlook settings by selecting the File tab, then going to Options > Advanced and checking the box under Affected users can also use the new Outlook email client or Outlook Web Access (OWA), which are not affected by this bug, or create a new Outlook profile.
The Blue Report 2026 measures defenses technique by technique across 338 million simulations run in customer production environments.
Since the start of the year, Microsoft has also resolved known issues that prevented some classic Outlook users from sending emails via Outlook.com and rendered the classic Outlook client unusable when enabling the Microsoft Teams Meeting Add-in.
Now, Microsoft says it has finally resolved this classic Outlook issue, blaming it on a bug that prevented Outlook from retrieving some account information from the user's Outlook profile.
"We fixed an issue in classic Outlook that could cause the Copilot entry point to be missing from the navigation pane when required account information could not be retrieved from the user’s Outlook profile.
The Copilot button might be missing for several different reasons, including licensing, Microsoft 365 app configuration, update channel, privacy settings, or other environmental factors," an update to the original support document reads .
What happened
Microsoft has fixed a known issue that removed the Copilot Chat and Copilot buttons in the classic Outlook desktop mail client for some Windows users.
As explained in an updated support document , affected users with the Copilot Chat (Basic) license or a Microsoft 365 Copilot (Premium) account no longer saw Copilot buttons in the side navigation and above the ribbon.
Those impacted by this experienced one or more of the following issues: Microsoft first announced in June that it had fixed the bug with a service change, but last month it said it had started investigating again after recent updates caused it to resurface.
What changed
Microsoft also shared a temporary workaround for those still affected by this known issue, which requires enabling the option in classic Outlook settings by selecting the File tab, then going to Options > Advanced and checking the box under Affected users can also use the new Outlook email client or Outlook Web Access (OWA), which are not affected by this bug, or create a new Outlook profile.
The Blue Report 2026 measures defenses technique by technique across 338 million simulations run in customer production environments.
Since the start of the year, Microsoft has also resolved known issues that prevented some classic Outlook users from sending emails via Outlook.com and rendered the classic Outlook client unusable when enabling the Microsoft Teams Meeting Add-in.
Who is affected
Now, Microsoft says it has finally resolved this classic Outlook issue, blaming it on a bug that prevented Outlook from retrieving some account information from the user's Outlook profile.
"We fixed an issue in classic Outlook that could cause the Copilot entry point to be missing from the navigation pane when required account information could not be retrieved from the user’s Outlook profile.
Response
The Copilot button might be missing for several different reasons, including licensing, Microsoft 365 app configuration, update channel, privacy settings, or other environmental factors," an update to the original support document reads .
Attribution
BleepingComputer: Microsoft has fixed a known issue that removed the Copilot Chat and Copilot buttons in the classic Outlook desktop mail client for some Windows users.
What to watch next
Watch for revised vendor guidance, fixed versions and mitigation updates.