To stop Outlook classic from auto-filling the wrong Gmail account and allow signing in with the correct Google account, clear the existing Gmail sign-in and then re-add it using the updated sign-in flow.
- Remove the existing Gmail account from the Outlook profile
- In classic Outlook, go to File > Account Settings > Account Settings.
- On the Email tab, select the Gmail account that is auto-populating.
- Choose Remove.
- Make sure Gmail is configured to allow IMAP
- In a browser, sign in to the Gmail account that should be used.
- Go to Settings > See all settings > Forwarding and POP/IMAP.
- Under IMAP access, select Enable IMAP.
- Select Save Changes.
- Ensure Outlook is on a build that uses the new Google sign-in window
- In Outlook, select File > Office Account.
- Select Update Options > Update Now to move to a build that includes the updated Google sign-in behavior described for Outlook for Microsoft 365.
- Add the Gmail account again so Outlook uses the Google sign-in page
- In Outlook, go to File > Add Account.
- Enter the Gmail address that should be used and continue.
- Outlook should open a separate browser window for Google sign-in (per the updated fix). Sign in with the correct Gmail account in that browser window.
If Outlook still auto-selects the wrong Google identity in the browser, sign out of Google in the browser first, then repeat step 4 so the correct account can be chosen.
If IMAP is not enabled on the Gmail side, Outlook can show errors like “We weren’t able to set up your Google account with IMAP. You may need to make changes to your Gmail settings,” so ensuring IMAP is enabled is required.
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