By connecting a Yahoo! to your Facebook account, you can reproduce your Yahoo! effectively. To do this, you need to go to your Yahoo! account settings. on a desktop computer. Since October 2016, you cannot link your Facebook account with your Yahoo! via the Yahoo! mobile app.
Step
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Step 1. Go to the Yahoo
. If you're not logged into your account, type in your username and password to access your email account.
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Step 2. Click Mail
It's in the upper-right corner of the Yahoo! page.
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Step 3. Click the settings menu icon or “Settings” (gear button)
You can find it in the top right corner of the Yahoo! inbox page.
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Step 4. Click Settings
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Step 5. Click Accounts
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Step 6. Click “Connect” next to the Facebook option
You will be asked to log into your Facebook account first if you haven't already.
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Step 7. Click Continue as [Your Name]
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Step 8. Click OK
Now, Yahoo! and your Facebook is connected!