This solution for POP Yahoo! Mail Plus with Microsoft Outlook 2002 (XP) and 2003.

If you want to POP your Yahoo! Mail Plus into Outlook 2002 or 2003, here’s how:
From the Tools menu, select “Email Accounts.”
Select the radio button next to “Add a new email account” and click the “Next” button.
Select the radio button next to “POP3″ and click the “Next” button.
Enter the following information:
a. User Information
Your Name: Enter your name as you’d like it to appear in the “From” field of your outgoing messages.
Email Address: Enter your full Yahoo! Mail address—for example, myyahooid@yahoo.com.
b. Server Information

1. Incoming mail server (POP3): plus.pop.mail.yahoo.com
2. Outgoing mail server (SMTP): plus.smtp.mail.yahoo.com

c. Login Information

User Name: Enter your Yahoo! ID and suffix (although the wizard will put in your email address without the suffix, we’ve found that you should use the full address—for example, myyahooid@yahoo.com).
Password: Enter your Yahoo! password.
Do not check the box next to “Log on using Secure Password Authentication (SPA).”
Click the “More Settings” box and select the “Outgoing Server” tab.
Check the box next to “My outgoing server (SMTP) requires authentication.”
Click the “Advanced” tab.

Under “Incoming Server (POP3)”, check the box next to “This server requires an encrypted connection (SSL)”. The port number in the “Incoming Server (POP3)” field should automatically change from 110 to 995. If it doesn’t, make sure the port number is set to 995.
Under “Outgoing Server (SMTP)”, check the box next to “This server requires an encrypted connection (SSL). Enter port number “465” in the “Outgoing Server (SMTP)” field.
If you’d like to keep a copy of your email messages on the Yahoo! Mail server, click the “Advanced” tab. Check the box next to “Leave a copy of messages on the server.” If you want to delete your messages from the Yahoo! Mail server after viewing them in Outlook, don’t check the box.
Click the “OK” button.
Click the “Next” button on the Email Account Wizard, then click “Finished.”

Troubleshooting instructions.

If you followed the above configuration steps, you should be all set. However, if you cannot send or receive mail with your email client, try the following tips.

The Yahoo! Mail SMTP server requires authentication. Make sure you have enabled SMTP authentication. To turn this setting on, follow these steps:
Click “Tools,” then select “Email Accounts.”
Select “View or change existing email accounts” and click “Next.”
Select your Yahoo! Mail account and click the “Change” button on the right.
Click the “More Settings…” button in the bottom-right corner of the Email Accounts window.
In the Internet Email Settings window, click the “Outgoing Server” tab. Ensure that the box is checked next to “My outgoing server (SMTP) requires authentication.”
Click the “Advanced” tab and ensure that you have not selected “This server requires a secure connection (SSL)” under the incoming (POP3) or outgoing (SMTP) port settings.

To control deletion of messages from the Yahoo! Mail Server, follow these steps:

From the Tools menu, choose “Email Accounts.”
Select the radio button next to “Edit an existing account” and click the “Next” button.
Double-click the Yahoo! account.
Select the “Advanced” tab.

In the Delivery section at the bottom of the window, check “Leave a copy of messages on server” if you want to save your Yahoo! Mail messages on both the Yahoo! Mail server and on your local computer. If you want your messages to be deleted from the Yahoo! Mail server after you have received them in Outlook, do not check this box.

We strongly recommend that you enable SSL for both POP and SMTP, as detailed in the above instructions. This will ensure that your Yahoo! ID, password and email messages are transmitted securely between your mail client and the Yahoo! servers. However, if you choose to not use SSL for SMTP, your email client will likely default the SMTP port to 25. If your ISP blocks port 25 or if you’re unable to send email, then you will need to use port 587 when sending via Yahoo!’s SMTP server. To make this change, please follow the directions below:

From the “Tools” menu, select “Accounts”
Select your Yahoo! POP account and click on the “Properties” button
Click on the “Advanced” tab
Next to “Outgoing server (SMTP), change port 25 to 587
Click “Apply”, then click “OK” and “Close”

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