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Fix POP or IMAP client sending and receiving issues

Third-party email clients like Outlook or Apple Mail use POP or IMAP to connect to your Yahoo account. Though this is designed to work seamlessly in the background, there may be reasons why the connection could fail and your messages aren't sent or received. To fix these issues, follow the troubleshooting below in order.

Check your account

Address any prompts or issues you see when signing in on a desktop before trying to sign in on a third-party email app, then send a test message.

  1. Sign in to Yahoo Mail from a web browser.
  2. Compose a new email and add your own address in the "To" field.
  3. Send the email.
  4. Wait up to five minutes to see if it arrives.

Verify the POP or IMAP settings

Confirm app is configured with the correct POP settings or IMAP settings for Yahoo Mail. Sometimes even if the info seems correct, the data the app saved could be corrupt or contain hidden invalid characters. Delete your Yahoo account from the app and re-add it to be sure. If you need specific instructions for your app, contact its manufacturer.

Try some basic troubleshooting

Create and use an app password - This is required if you've enabled Yahoo account key or two-step verification.

Check for extra email address - An unverified email address can cause a 553 error when sending from a third-party app.

Update your app - If you receive an error message like "Server password has changed" or "Authentication failed," your app might be outdated. The app likely has outdated security protocols and are disabled by default. Either update the app or grant temporary access in your account settings.

Check for software blocking ports

Firewalls, antivirus software, and network protocols have the ability to block ports. If any of our ports (995, 465, or 587) are blocked, the app can't connect to our servers. Check with your Internet Service Provider or your security software's manufacturer to learn how to check for and unblock ports.

Contact your app manufacturer or use a different app

If you've verified that your account is working outside of the app and you've checked the other possible solutions, then there's something wrong with the app you're using. The app manufacturer may have additional troubleshooting steps to try. Alternatively, use a different third-party email app.