Hi my name is ***** ***** I can assist you. There is a setting in the Yahoo! Web Account that allows "less-secure" apps to have access to your Yahoo! Mail. If you go to yahoo.com and hover on your name in the top right corner, click on Account Info. There will be a place for "Manage apps and website connections". Under this page is a setting to turn on Access to Less-Secure Applications. After you turn this on, Outlook will work. Let me know if that doesn't work.
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