If Yahoo Mail does not work with Outlook, there may be a setting or setup issue. This implies you'll need to properly set up Yahoo mail with Outlook. Make sure you're using the most recent versions of both email services, as this problem can potentially be caused by an older version.

1. Log in to login.yahoo.com/account/security and enable the settings at the bottom.
2. Open Outlook and select File > Add Account Now from the File menu. Select Manual Setup or Additional Server Types and click Next.
3. After that, select POP or IMAP from the drop-down menu and click  on Next
4. Within POP and IMAP account settings, fill in Your Name and Fill Email address
5. Choose IMAP as the Account Type, and the Incoming Mail Server should be set to imap.mail.yahoo.com, while the Outgoing Mail Server should be set to smtp.mail.yahoo.com.

1. Enable the Outgoing Server option on the Outgoing Server tab. My outgoing server requires authentication and uses the same configuration as my inbound mail server.
2. Set Incoming server in the Advanced tab for port settings.
3. Set the Outgoing server to 993 with SSL encryption, and then IMAP to 993.
4. When finished, SMTP to 587 with TLS encryption and click Ok and then Next.
5. If the account is properly logged in, click Close.

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