To stop using Yahoo Mail in Outlook for Windows and remove that account from Outlook (which also stops Edge from opening it via Outlook), remove the Yahoo account from Outlook itself. Use the steps that match the Outlook version in use.
Classic Outlook for Windows (Outlook 2016/2019/Microsoft 365 classic)
- Open Outlook.
- Select File (top-left).
- Select Account Settings > Account Settings.
- On the Email tab, select the Yahoo account.
- Select Remove.
- Confirm any warning that offline cached content for that account will be deleted, then select Yes.
This removes the Yahoo account from Outlook but does not delete the Yahoo account itself; Yahoo Mail remains accessible via the Yahoo website.
New Outlook for Windows
- Open Outlook.
- On the View tab, select View settings, or on the File tab, select Account info.
- Select Accounts > Your accounts.
- Under Email accounts, find the Yahoo account and select Manage next to it.
- Select Remove.
- For non-Microsoft accounts like Yahoo, choose whether to remove the account from only this device or from all devices where it was added to Outlook.
If Outlook is stuck in a loop and will not open normally, start Outlook with a different or new account (if prompted), then use the steps above to remove the Yahoo account. Once removed, Outlook and Edge will no longer try to use that Yahoo mailbox through Outlook.
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